Buy BOOKS at Discounted Price

Data Handling

Class 8th Mathematics NCERT Exemplar Solution
Exercise
  1. The height of a rectangle in a histogram shows theA. Width of the class B. Upper…
  2. A geometric representation showing the relationship between a whole and its parts…
  3. In a pie chart, the total angle at the center of the circle isA. 180° B. 360° C.…
  4. The range of the data 30, 61, 55, 56, 60, 20, 26, 46, 28, 56 isA. 26 B. 30 C. 41…
  5. Which of the following is not a random experiment?A. Tossing a coin B. Rolling a…
  6. What is the probability of choosing a vowel from the alphabets?A. 21/26 B. 5/26 C.…
  7. In a school only, 3 out of 5 students can participate in a competition. What is…
  8. Observe the pie chart given below and answer question based on it. Which colour…
  9. Observe the pie chart given below and answer question based on it. If 400 students…
  10. Observe the pie chart given below and answer question based on it. Which of the…
  11. Listed below are the temperature in °C for 10 days. -6, -8, 0, 3, 2, 0, 1, 5, 4,…
  12. Ram put some buttons on the table. There were 4 blue, 7 red, 3 black and 6 white…
  13. Rahul, Varun and Yash are playing a game of spinning a coloured wheel. Rahul wins…
  14. In a frequency distribution with classes 0 -10, 10 -20 etc., the size of the…
  15. A coin is tossed 200 times and head appeared 120 times. The probability of…
  16. Data collected in a survey shows that 40% of the buyers are interested in buying…
  17. Monthly salary of a person is Rs. 15000. The central angle of the sector…
  18. The following pie chart gives the distribution of constituents in the human body.…
  19. Rohan and Shalu are playing with 5 cards as shown in the figure. What is the…
  20. The following pie chart represents the distribution of proteins in parts of a…
  21. What is the central angle of the sector (in the above pie chart) representing…
  22. What is the central angle of the sector (in the above pie chart) representing…
  23. A coin is tossed 12 times and the outcomes are observed as shown below: 0000 The…
  24. Total number of outcomes, when a ball is drawn from a bag which contains 3 red, 5…
  25. A graph showing two sets of data simultaneously is known asA. Pictograph B.…
  26. Size of the class 150 -175 isA. 150 B. 175 C. 25 D. -25
  27. In a throw of a dice, the probability of getting the number 7 isA. 1/2 B. 1/6 C.…
  28. Data represented using circles is known asA. Bar graph B. Histogram C. Pictograph…
  29. Tally marks are used to findA. Class intervals B. Range C. Frequency D. Upper…
  30. Upper limit of class interval 75 -85 isA. 10 B. -10 C. 75 D. 85
  31. Numbers 1 to 5 are written on separate slips, i.e one number on one slip and put…
  32. A glass jar contains 6 red, 5 green, 4 blue and 5 yellow marbles of same size.…
  33. A coin is tossed two times. The number of possible outcomes isA. 1 B. 2 C. 3 D. 4…
  34. A coin is tossed three times. The number of possible outcomes isA. 3 B. 4 C. 6 D.…
  35. A dice is tossed two times. The number of possible outcomes isA. 12 B. 24 C. 36…
  36. Data available in an unorganised form is called __________ data. In question,…
  37. In the class interval 20 - 30, the lower class limit is __________. In question,…
  38. In the class interval 26 - 33, 33 is known as __________. In question, fill in…
  39. The range of the data 6, 8, 16, 22, 8, 20, 7, 25 is __________. In question, fill…
  40. A pie chart is used to compare __________ to a whole. In question, fill in the…
  41. In the experiment of tossing a coin one time, the outcome is either __________ or…
  42. When a dice is rolled, the six possible outcomes are __________. In question,…
  43. Each outcome or a collection of outcomes in an experiment makes an __________. In…
  44. An experiment whose outcomes cannot be predicted exactly in advance is called a…
  45. The difference between the upper and lower limit of a class interval is called…
  46. The sixth class interval for a grouped data whose first two class intervals are…
  47. Histogram given on the right shows the number of people owning the different…
  48. Histogram given on the right shows the number of people owning the different…
  49. Histogram given on the right shows the number of people owning the different…
  50. Histogram given on the right shows the number of people owning the different…
  51. The number of times a particular observation occurs in a given data is called its…
  52. When the number of observations is large, the observations are usually organized…
  53. The total number of outcomes when a coin is tossed is __________. In question,…
  54. The class size of the interval 80 - 85 is __________. In question, fill in the…
  55. In a histogram __________ are drawn with width equal to a class interval without…
  56. When a dice is thrown, outcomes 1, 2, 3, 4, 5, 6 are equally __________. In…
  57. In a histogram, class intervals and frequencies are taken along __________ axis…
  58. In the class intervals 10 -20, 20 -30, etc., respectively, 20 lies in the class…
  59. In a pie chart a whole circle is divided into sectors. In question, state whether…
  60. The central angle of a sector in a pie chart cannot be more than 180°. In…
  61. Sum of all the central angles in a pie chart is 360°. In question, state whether…
  62. In a pie chart two central angle can be of 180°. In question, state whether the…
  63. In a pie chart two or more central angles can be equal. In question, state…
  64. Getting a prime number on throwing a die is an event. In question, state whether…
  65. Using the following frequency table, 9 students got full marks. In question,…
  66. Using the following frequency table, The frequency of less than 8 marks is 29. In…
  67. Using the following frequency table, The frequency of more than 8 marks is 21. In…
  68. Using the following frequency table, 10 marks has the highest frequency. In…
  69. If the fifth class interval is 60 - 65, fourth class interval is 55 - 60, then…
  70. From the histogram given on the right, we can say that 1500 males above the age…
  71. The class size of the class interval m 60 - 68 is In question, state whether the…
  72. On throwing a dice once, the probability of occurence of an even number is 1/2.…
  73. On throwing a dice once, the probability of occurence of a composite number is…
  74. From the given pie chart, we can infer that production of Manganese is least in…
  75. One or more outcomes of an experiment make an event. In question, state whether…
  76. The probability of getting number 6 in a throw of a dice is 1/6. Similarly the…
  77. The probability of getting a prime number is the same as that of a composite…
  78. In a throw of a dice, the probability of getting an even number is the same as…
  79. To verify pythagoras theorem is a random experiment. In question, state whether…
  80. The following pictorial representation of data is a histogram. In question, state…
  81. Given below is a frequency distribution table. Read it and answer the questions…
  82. The top speeds of thirty different land animals have been organized into a…
  83. Given below is a pie chart showing the time spend by a group of 350 children in…
  84. The pie chart on the right shows the result of a survey carried out to find the…
  85. A dice is rolled once. What is the probability that the number on top will be (a)…
  86. Classify the following statements under appropriate headings. (a) Getting the sum…
  87. Study the pie chart given below depicting the marks scored by a student in an…
  88. Ritwik draws a ball from a bag that contains white and yellow balls. The…
  89. Look at the histogram below and answer the questions that follow. (a) How many…
  90. Following are the number of members in 25 families of a village: 6, 8, 7, 7, 6,…
  91. Draw a histogram to represent the frequency distribution in question 91.…
  92. The marks obtained (out of 20) by 30 students of a class in a test are as…
  93. Prepare a histogram from the frequency distribution table obtained in question…
  94. The weights (in kg) of 30 students of a class are: 39, 38, 36, 38, 40, 42, 43,…
  95. Shoes of the following brands are sold in Nov. 2007 at a shoe store. Construct a…
  96. The following pie chart depicts the expenditure of a state government under…
  97. The following data represents the different number of animals in a zoo. Prepare a…
  98. Playing cards (a) From a pack of cards the following cards are kept face down:…
  99. Construct a frequency distribution table for the following weights (in grams) of…
  100. Complete the following table: Find the total number of persons whose weights are…
  101. Draw a histogram for the following data.
  102. In a hypothetical sample of 20 people, the amount of money (in thousands of…
  103. The below histogram shows the number of literate females in the age group of 10…
  104. The following histogram shows the frequency distribution of teaching experiences…
  105. In a district, the number of branches of different banks is given below: Draw a…
  106. For the development of basic infrastructure in a district, a project of Rs 108…
  107. In the time table of a school, periods allotted per week to different teaching…
  108. A survey was carried out to find the favourite beverage preferred by a certain…
  109. The following data represents the approximate percentage of water in various…
  110. At a Birthday Party, the children spin a wheel to get a gift. Find the…
  111. Sonia picks up a card from the given cards. Calculate the probability of getting…
  112. Identify which symbol should appear in each sector in.
  113. Identify which symbol should appear in each sector.
  114. A financial counselor gave a client this pie chart describing how to budget his…
  115. Following is a pie chart showing the amount spent in rupees (in thousands) by a…
  116. If a pair of coins is tossed, then the number of outcomes is 2. In question,…

Exercise
Question 1.

The height of a rectangle in a histogram shows the
A. Width of the class

B. Upper limit of the class

C. Lower limit of the class

D. Frequency of the class




Answer:

The height of a rectangle in a histogram shows the number of time the particular observation occurred in the data that is frequency.


Hence, the height of a rectangle in a histogram shows the Frequency of the class.


Question 2.

A geometric representation showing the relationship between a whole and its parts is a
A. Pie chart

B. Histogram

C. Bar graph

D. Pictograph


Answer:

A pie chart is a circular statistical graphic which is divided into slices to illustrate numerical proportion. The circle is taken as a whole and the slices are its part.

Hence, a geometric representation showing the relationship between a whole and its parts is a Pie chart.


Question 3.

In a pie chart, the total angle at the center of the circle is
A. 180°

B. 360°

C. 270°

D. 90°


Answer:

The total angle at the center of the circle is always 360°.


Hence, in a pie chart, the total angle at the center of the circle is 360°.


Question 4.

The range of the data 30, 61, 55, 56, 60, 20, 26, 46, 28, 56 is
A. 26

B. 30

C. 41

D. 61


Answer:

Range of data = Maximum value in data – Minimum value in data

The maximum value in data is 61


And,


The minimum value in data is 20


⇒ Range of data = 61 – 20


⇒ Range of data = 41


Hence, the range of data is 41


Question 5.

Which of the following is not a random experiment?
A. Tossing a coin

B. Rolling a dice

C. Choosing a card from a deck of 52 cards

D. Throwing a stone from a roof of a building


Answer:

On throwing a stone from a roof of a building we know there is only one output that is the stone will fall down therefore it is not a random experiment.

But for tossing a coin, rolling a dice and choosing a card from a deck of 52 cards have more than one outputs therefore they are random experiments.


Hence, throwing a stone from a roof of a building is not a random experiment.


Question 6.

What is the probability of choosing a vowel from the alphabets?
A.

B.

C.

D.


Answer:

Total number of vowels = 5

⇒ Total number of favourable outcomes = 5


Total number of alphabets = 26


⇒ Total number of outcomes = 26




Hence, the probability of choosing a vowel from the alphabets is.


Question 7.

In a school only, 3 out of 5 students can participate in a competition.

What is the probability of the students who do not make it to the competition?
A. 0.65

B. 0.4

C. 0.45

D. 0.6


Answer:

Total number of students = 5

⇒ Total number of outcomes = 5


Number of students that can participate = 3


⇒ Number of students that cannot participate = 5 – 3 = 2


⇒ Total number of favourable outcomes = 2




⇒ Probability = 0.4


Hence, the probability of the students who do not make it to the competition is 0.4.


Question 8.

Students of a class voted for their favorite colour and a pie chart was prepared based on the data collected.

Observe the pie chart given below and answer question based on it.

Which colour received of the votes?


A. Red

B. Blue

C. Green

D. Yellow


Answer:

Votes received by Blue = 25%



Votes received by Red = 35%




Votes received by Green = 20%




Votes received by Yellow = 14%




Votes received by Others = 6%




Hence, the color that received votes is yellow.


Question 9.

Students of a class voted for their favorite colour and a pie chart was prepared based on the data collected.

Observe the pie chart given below and answer question based on it.

If 400 students voted in all, then how many did vote ‘Others’ colour as their favourite?
A. 6

B. 20

C. 24

D. 40


Answer:

Total number of votes = 400

Votes received by Others = 6%


Votes received by Others = 6% of 400



Votes received by Others = 24


Hence, students that voted for ‘Others’ colour as their favourite is 24.


Question 10.

Students of a class voted for their favorite colour and a pie chart was prepared based on the data collected.

Observe the pie chart given below and answer question based on it.

Which of the following is a reasonable conclusion for the given data?
A. th student voted for blue colour

B. Green is the least popular colour

C. The number of students who voted for red colour is two times the number of students who voted for yellow colour

D. Number of students liking together yellow and green colour is approximately the same as those for red colour.


Answer:

Votes received by Red = 35%

Votes received by Green = 20%


Votes received by Yellow = 14%


Votes received by Yellow and Green = 20% + 14%


⇒ Votes received by Yellow and Green = 34%


Hence, Number of students liking together yellow and green colour (i.e., 34%) is approximately the same as those for red colour(i.e., 35%).


Question 11.

Listed below are the temperature in °C for 10 days.

–6, –8, 0, 3, 2, 0, 1, 5, 4, 4

What is the range of the data?
A. 8

B. 13°C

C. 10°C

D. 12°C


Answer:

Range of data = Maximum value in data – Minimum value in data

The maximum value in data is 5


And,


The minimum value in data is -8


⇒ Range of data = 5 – (-8)


⇒ Range of data = 13


Hence, the range of data is 13°C


Question 12.

Ram put some buttons on the table. There were 4 blue, 7 red, 3 black and 6 white buttons in all. All of a sudden, a cat jumped on the table and knocked out one button on the floor. What is the probability that the button on the floor is blue?
A.

B.

C.

D.


Answer:

Total number of buttons = 4 + 7 + 3 + 6

⇒ Total number of buttons = 20


⇒ Total number of outcomes = 20


Number of blue buttons = 4


⇒ Total number of favourable outcomes = 4





Hence, the probability that the button on the floor is blue is .


Question 13.

Rahul, Varun and Yash are playing a game of spinning a coloured wheel. Rahul wins if spinner lands on red. Varun wins if spinner lands on blue and Yash wins if it lands on green. Which of the following spinner should be used to make the game fair?
A.

B.

C.

D.


Answer:

In the figure iv, there are 2 equal portions of Red, 2 equal portions of Green and 2 equal portions of Blue, therefore, the game will be fair as each color will have same area.

Hence, figure iv should be used to make the game fair.


Question 14.

In a frequency distribution with classes 0 –10, 10 –20 etc., the size of the class intervals is 10. The lower limit of fourth class is
A. 40

B. 50

C. 20

D. 30


Answer:

First class = 0 – 10

Second class = 10 – 20


Third class = 20 – 30


Fourth class = 30 – 40


Hence, the lower limit of fourth class is 30.


Question 15.

A coin is tossed 200 times and head appeared 120 times. The probability of getting a head in this experiment is
A.

B.

C.

D.


Answer:

Total number of times coin tossed = 120

⇒ Total number of outcomes = 120


Number of times head appears = 200


⇒ Total number of favourable outcomes = 200





Hence, the probability of getting a head in this experiment is .


Question 16.

Data collected in a survey shows that 40% of the buyers are interested in buying a particular brand of toothpaste. The central angle of the sector of the pie chart representing this information is
A. 120°

B. 150°

C. 144°

D. 40°


Answer:

We know that,

Central angle of the pie chart = 360°


Buyers interested in buying a particular brand of toothpaste = 40%


Central angle of the sector = 40% of Central angle of the pie chart


⇒ Central angle of the sector = 40% of 360°



⇒ Central angle of the sector = 144°


Hence, the central angle of the sector of the pie chart representing this information is 144°.


Question 17.

Monthly salary of a person is Rs. 15000. The central angle of the sector representing his expenses on food and house rent on a pie chart is 60°. The amount he spends on food and house rent is
A. Rs. 5000

B. Rs. 2500

C. Rs. 6000

D. Rs. 9000


Answer:

We know that,

Central angle of the pie chart = 360°


Central angle of the sector of pie chart = 60°


Monthly salary of a person = Rs 15000






⇒ Amount spent on food and house rent = Rs 2500


Hence, the amount he spends on food and house rent is Rs 2500.


Question 18.

The following pie chart gives the distribution of constituents in the human body. The central angle of the sector showing the distribution of protein and other constituents is


A. 108°

B. 54°

C. 30°

D. 216°


Answer:

Protein = 16%

Other constituents = 14%


⇒ Protein and other constituents = 16% + 14%


⇒ Protein and other constituents = 30%



⇒ Central angle of sector = 108°


Hence, the central angle of the sector showing the distribution of protein and other constituents is 108°


Question 19.

Rohan and Shalu are playing with 5 cards as shown in the figure. What is the probability of Rohan picking a card without seeing, that has the number 2 on it?



(a)

B.

C.

D.


Answer:

Total number of cards = 5

⇒ Total number of outcomes = 5


⇒ Number of card with number 2 = 2


⇒ Total number of favourable outcomes = 2




Hence, the probability of the students who do not make it to the competition is .


Question 20.

The following pie chart represents the distribution of proteins in parts of a human body. What is the ratio of distribution of proteins in the muscles to that of proteins in the bones?


A. 3 : 1

B. 1 : 2

C. 1 : 3

D. 2 : 1


Answer:





Ratio of Protein in muscles to Protein in bones = 2: 1


Hence, the ratio of distribution of proteins in the muscles to that of proteins in the bones is 2: 1.


Question 21.

What is the central angle of the sector (in the above pie chart) representing skin and bones together?
A. 36°

B. 60°

C. 90°

D. 96°


Answer:






Therefore,



⇒ Central angle of sector with skin and bones = 96°


Hence, central angle of the sector representing skin and bones together is 96°


Question 22.

What is the central angle of the sector (in the above pie chart) representing hormones enzymes and other proteins.
A. 120°

B. 144°

C. 156°

D. 176°


Answer:








Therefore,



⇒ Central angle of sector = 144°


Hence, central angle of the sector representing hormones enzymes and other proteins is 144°.


Question 23.

A coin is tossed 12 times and the outcomes are observed as shown below:



The chance of occurrence of Head is
A.

B.

C.

D.


Answer:

Total number of tosses = 12

⇒ Total number of outcomes = 12


⇒ Number of heads = 5


⇒ Total number of favorable outcomes = 5




Hence, the chance of occurrence of Head is .


Question 24.

Total number of outcomes, when a ball is drawn from a bag which contains 3 red, 5 black and 4 blue balls is
A. 8

B. 7

C. 9

D. 12


Answer:

Total number of balls = 3 + 5 + 4

⇒ Total number of balls = 12


⇒ Total number of outcomes = 12


Hence, the total number of outcomes is 12.


Question 25.

A graph showing two sets of data simultaneously is known as
A. Pictograph

B. Histogram

C. Pie chart

D. Double bar graph


Answer:

A double bar graph is a graphical display of information using two bars besides each other at various heights. The bars can be arranged vertically or horizontally. We can use a double bar graph to compare two data groups.

A graph showing two sets of data simultaneously is known as Double bar graph.


Question 26.

Size of the class 150 –175 is
A. 150

B. 175

C. 25

D. –25


Answer:

Size of a class = Upper Limit – Lower Limit

⇒ Size of a 150 – 175 = 175 – 150


⇒ Size of a 150 – 175 = 25


Hence, the size of the class 150 –175 is 25.


Question 27.

In a throw of a dice, the probability of getting the number 7 is
A.

B.

C. 1

D. 0


Answer:

In a dice, there are only 6 numbers that are, 1, 2, 3, 4, 5 and 6.

Therefore, there is no possibility of 7.


Hence, the probability of getting the number 7 is 0.


Question 28.

Data represented using circles is known as
A. Bar graph

B. Histogram

C. Pictograph

D. Pie chart


Answer:

Pie chart is a type of graph in which a circle is divided into sectors that each represents a proportion of the whole.

Hence, the data represented using circles is known as Pie chart.


Question 29.

Tally marks are used to find
A. Class intervals

B. Range

C. Frequency

D. Upper limit


Answer:

Tally marks are a quick way of keeping track of numbers in groups of five. One vertical line is made for each of the first four numbers; the fifth number is represented by a diagonal line across the previous four.

Hence, they are used to find Frequency.


Question 30.

Upper limit of class interval 75 –85 is
A. 10

B. –10

C. 75

D. 85


Answer:

The lower value of class interval (i.e., 75 here) is called lower limit and the upper value of class interval (i.e., 85 here) is called upper limit.

Hence, the upper limit of class interval 75 –85 is 85.


Question 31.

Numbers 1 to 5 are written on separate slips, i.e one number on one slip and put in a box. Wahida pick a slip from the box without looking at it. What is the probability that the slip bears an odd number?
A.

B.

C.

D.


Answer:

Odd numbers between 1 and 5 are 1, 3 and 5

∴ Total number of odd numbers = 3


⇒ Total number of favourable outcomes = 3


⇒ All Numbers = 5


⇒ Total number of outcomes = 5




Hence, the probability that the slip bears an odd number is


Question 32.

A glass jar contains 6 red, 5 green, 4 blue and 5 yellow marbles of same size. Hari takes out a marble from the jar at random. What is the probability that the chosen marble is of red colour?
A.

B.

C.

D.


Answer:

Total number of marbles = 6 + 5 + 4 + 5

⇒ Total number of odd numbers = 20


⇒ Total number of outcomes = 20


⇒ Number of red marbles = 6


⇒ Total number of favourable outcomes = 6





Hence, the probability that the slip bears an odd number is.


Question 33.

A coin is tossed two times. The number of possible outcomes is
A. 1

B. 2

C. 3

D. 4


Answer:

When a coin is tossed two times the possible outcomes are

HH – Two heads


HT – First head and second tail


TH – First tail and second tail


HH – Two tails


Therefore,


The sample space is {HH, HT, TH, TT} = 4


Hence, the number of possible outcomes is 4.


Question 34.

A coin is tossed three times. The number of possible outcomes is
A. 3

B. 4

C. 6

D. 8


Answer:

When a coin is tossed two times the possible outcomes are HHH, HHT, HTH, THH, HTT, TTH, THT and TTT.

Therefore,


The sample space is {HHH, HHT, HTH, THH, HTT, TTH, THT, TTT} = 8


Hence, the number of possible outcomes is 8.


Question 35.

A dice is tossed two times. The number of possible outcomes is
A. 12

B. 24

C. 36

D. 30


Answer:

When a dice is tossed two times,

The sample space is


{(1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6),


(2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6),


(3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6),


(4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6),


(5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6),


(6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)} = 36


Hence, the number of possible outcomes is 36.


Question 36.

In question, fill in the blanks to make the statements true.

Data available in an unorganised form is called __________ data.


Answer:

Raw

Raw data is the data that has not been processed for use.


Hence, Data available in an unorganised form is called Raw data.



Question 37.

In question, fill in the blanks to make the statements true.

In the class interval 20 – 30, the lower class limit is __________.


Answer:

20

The lower value of class interval (i.e., 20 here) is called lower limit and the upper value of class interval (i.e., 30 here) is called upper limit.


Hence, the upper limit of class interval 20 – 30 is 30 .



Question 38.

In question, fill in the blanks to make the statements true.

In the class interval 26 – 33, 33 is known as __________.


Answer:

Upper Limit

The lower value of class interval (i.e., 26 here) is called lower limit and the upper value of class interval (i.e., 33 here) is called upper limit.


Hence, in the class interval 26 – 33, 33 is known as Upper Limit.



Question 39.

In question, fill in the blanks to make the statements true.

The range of the data 6, 8, 16, 22, 8, 20, 7, 25 is __________.


Answer:

19

Range of data = Maximum value in data – Minimum value in data


The maximum value in data is 25


And,


The minimum value in data is 6


⇒ Range of data = 25 – 6


⇒ Range of data = 19


Hence, the range of the data 6, 8, 16, 22, 8, 20, 7, 25 is 19.



Question 40.

In question, fill in the blanks to make the statements true.

A pie chart is used to compare __________ to a whole.


Answer:

A part

A pie chart is a circular statistical graphic which is divided into slices to illustrate numerical proportion. The circle is taken as a whole and the slices are its part.


It is a geometric representation showing the relationship between a whole and its parts is a Pie chart.


Hence, a pie chart is used to compare a part to a whole.



Question 41.

In question, fill in the blanks to make the statements true.

In the experiment of tossing a coin one time, the outcome is either __________ or __________.


Answer:

head or tail

A coin has only 2 faces head and tail, therefore, while tossing it only one of the two will appear.


Hence, in the experiment of tossing a coin one time, the outcome is either head or tail.



Question 42.

In question, fill in the blanks to make the statements true.

When a dice is rolled, the six possible outcomes are __________.


Answer:

1, 2, 3, 4, 5 and 6

A dice has 6 faces 1, 2, 3, 4, 5 and 6 therefore, while tossing it only one of the six will appear.


Hence, when a dice is rolled, the six possible outcomes are 1, 2, 3, 4, 5 and 6.



Question 43.

In question, fill in the blanks to make the statements true.

Each outcome or a collection of outcomes in an experiment makes an __________.


Answer:

Event

An event is a set of outcomes of an experiment (a subset of the sample space) to which a probability is assigned.


Hence, each outcome or a collection of outcomes in an experiment makes an Event.



Question 44.

In question, fill in the blanks to make the statements true.

An experiment whose outcomes cannot be predicted exactly in advance is called a __________ experiment.


Answer:

Random

An experiment is said to be random if it has more than one possible outcome.


Hence, an experiment whose outcomes cannot be predicted exactly in advance is called a Random experiment.



Question 45.

In question, fill in the blanks to make the statements true.

The difference between the upper and lower limit of a class interval is called the __________ of the class interval.


Answer:

Size

The size of a class interval is range of the class that is, the difference between the upper and lower limit of a class interval.


Hence, the difference between the upper and lower limit of a class interval is called the size of the class interval.



Question 46.

In question, fill in the blanks to make the statements true.

The sixth class interval for a grouped data whose first two class intervals are 10 – 15 and 15 – 20 is __________.


Answer:

35 – 40

First interval = 10 – 15


Second interval = 15 – 20


Clearly,


Size of class interval = 5


Therefore,


Third interval = 20 – 25


Fourth interval = 25 – 30


Fifth interval = 30 – 35


Sixth interval = 35 – 40


Hence, the sixth-class interval for a grouped data whose first two class intervals are 10 – 15 and 15 – 20 is 35 – 40.



Question 47.

In question, fill in the blanks to make the statements true.

Histogram given on the right shows the number of people owning the different number of books.



The total number of people surveyed is __________.


Answer:

35

Number of people = 8 + 14 + 5 + 6 + 2


⇒ Number of people = 35


Hence, total number of people surveyed is 35.



Question 48.

In question, fill in the blanks to make the statements true.

Histogram given on the right shows the number of people owning the different number of books.



The number of people owning books more than 60 is __________.


Answer:

8

Number of people owning books more than 60 = 6 + 2


⇒ Number of people owning books more than 60 = 8


Hence, total number of people owning books more than 60 is 8.



Question 49.

In question, fill in the blanks to make the statements true.

Histogram given on the right shows the number of people owning the different number of books.



The number of people owning books less than 40 is __________.


Answer:

22

Number of people owning books less than 40 = 8 + 14


⇒ Number of people owning books less than 40 = 22


Hence, total number of people owning books less than 40 is 22.



Question 50.

In question, fill in the blanks to make the statements true.

Histogram given on the right shows the number of people owning the different number of books.



The number of people having books more than 20 and less than 40 is __________.


Answer:

14

Number of people owning books more than 20 but less than 40 = 14


Hence, total number of people having books more than 20 and less than 40 is 14.



Question 51.

In question, fill in the blanks to make the statements true.

The number of times a particular observation occurs in a given data is called its __________.


Answer:

Frequency

The frequency of an event is the number of times the event occurred in an experiment or study.


Hence, the number of times a particular observation occurs in a given data is called its frequency.



Question 52.

In question, fill in the blanks to make the statements true.

When the number of observations is large, the observations are usually organized in groups of equal width called __________.


Answer:

Class Intervals

Class Interval is the size of each class into which a range of a variable is divided.


Hence, when the number of observations is large, the observations are usually organized in groups of equal width called Class Intervals.



Question 53.

In question, fill in the blanks to make the statements true.

The total number of outcomes when a coin is tossed is __________.


Answer:

Two

When a coin is tossed there are only 2 outcomes head and tail.


Hence, the total number of outcomes when a coin is tossed is 2.



Question 54.

In question, fill in the blanks to make the statements true.

The class size of the interval 80 – 85 is __________.


Answer:

5

The size of a class interval = Upper Limit – Lower Limit


⇒ The size of a class interval = 85 – 80


⇒ The size of a class interval = 5


Hence, class size of the interval 80 – 85 is 5.



Question 55.

In question, fill in the blanks to make the statements true.

In a histogram __________ are drawn with width equal to a class interval without leaving any gap in between.


Answer:

bars


These are the histogram bars that have width that is equal to class intervals.


Hence, in a histogram bars are drawn with width equal to a class interval without leaving any gap in between.



Question 56.

In question, fill in the blanks to make the statements true.

When a dice is thrown, outcomes 1, 2, 3, 4, 5, 6 are equally __________.


Answer:

likely

When a dice is thrown 1, 2, 3, 4, 5 and 6 have all equal chance of appearance. That is they are equally likely.


Hence, when a dice is thrown, outcomes 1, 2, 3, 4, 5, 6 are equally likely.



Question 57.

In question, fill in the blanks to make the statements true.

In a histogram, class intervals and frequencies are taken along __________ axis and __________ axis.


Answer:

X, Y

There are class intervals on the X–axis and frequencies on the Y– axis.


Hence, in a histogram, class intervals and frequencies are taken along x axis and y axis.



Question 58.

In question, fill in the blanks to make the statements true.

In the class intervals 10 –20, 20 –30, etc., respectively, 20 lies in the class __________.


Answer:

20 – 30

Numbers that lie in 10 – 20 are 10, 11, ……, 19


And,


Numbers that lie in 20 – 30 are 20, 21, ……, 29


Hence, in the class intervals 10 – 20 , 20 – 30, etc., respectively, 20 lies in the class 20 – 30.



Question 59.

In question, state whether the statements are true (T) or false (F).

In a pie chart a whole circle is divided into sectors.


Answer:

True

A pie chart is a type of graph in which a circle is divided into sectors that each represents a proportion of the whole.


Hence, the statement is true.



Question 60.

In question, state whether the statements are true (T) or false (F).

The central angle of a sector in a pie chart cannot be more than 180°.


Answer:

False

The sum of all central angles of a pie chart is 360° just like any circle, therefore the central angle of a sector in a pie chart cannot be more than 360° but it can be more than 180°.


Hence, the statement is false.



Question 61.

In question, state whether the statements are true (T) or false (F).

Sum of all the central angles in a pie chart is 360°.


Answer:

True

A pie chart is a circular graph, therefore just like any other circle the sum of all its central angles is 360°.


Hence, the statement is true.



Question 62.

In question, state whether the statements are true (T) or false (F).

In a pie chart two central angle can be of 180°.


Answer:

True

The sum of all central angles of a pie chart does not exceed 360°.


∵ 180° + 180° = 360° (i.e., it does not exceed 360°)


Therefore, two central angles can be of 180°.


Hence, the statement is true.



Question 63.

In question, state whether the statements are true (T) or false (F).

In a pie chart two or more central angles can be equal.


Answer:

True

Yes in a pie chart, two or more central angles can be equal.


Hence, the statement is true.



Question 64.

In question, state whether the statements are true (T) or false (F).

Getting a prime number on throwing a die is an event.


Answer:

True

An event is a set of outcomes of an experiment (a subset of the sample space) to which a probability is assigned.


Therefore, getting a prime number on throwing a die is an event.


Hence, the statement is true.



Question 65.

In question, state whether the statements are true (T) or false (F).

Using the following frequency table,



9 students got full marks.


Answer:

True

The frequency of marks 10 is 9


Therefore, 9 students got full (10) marks.


Hence, the statement is true.



Question 66.

In question, state whether the statements are true (T) or false (F).

Using the following frequency table,



The frequency of less than 8 marks is 29.


Answer:

False

Frequency of marks 4 = 5


Frequency of marks 5 = 10


Frequency of marks 7 = 8


⇒ Frequency of marks less than 8 = 5 + 10 + 8


⇒ Frequency of marks less than 8 = 23


Therefore, the frequency of less than 8 marks is 23.


Hence, the statement is false.



Question 67.

In question, state whether the statements are true (T) or false (F).

Using the following frequency table,



The frequency of more than 8 marks is 21.


Answer:

True

Frequency of marks 9 = 12


Frequency of marks 10 = 9


⇒ Frequency of marks more than 8 = 12 + 9


⇒ Frequency of marks more than 8 = 21


Therefore, the frequency of more than 8 marks is 21.


Hence, the statement is true.



Question 68.

In question, state whether the statements are true (T) or false (F).

Using the following frequency table,



10 marks has the highest frequency.


Answer:

False

Explanation:


Frequency of marks 9 = 12


Frequency of marks 10 = 9


∵ 12 > 9


⇒ Frequency of marks 9 > Frequency of marks 10


Therefore, 9 marks has the highest frequency.


Hence, the statement is false.



Question 69.

In question, state whether the statements are true (T) or false (F).

If the fifth class interval is 60 – 65, fourth class interval is 55 – 60, then the first class interval is 45 –50.


Answer:

False

Explanation:


Fifth class interval = 60 – 65


Fourth class interval = 55 – 60


Third class interval = 50 – 55


Second class interval = 45 – 50


First class interval = 40 – 45


Therefore, the first class interval is 40 – 45.


Hence, the statement is false.



Question 70.

In question, state whether the statements are true (T) or false (F).

From the histogram given on the right, we can say that 1500 males above the age of 20 are literate.



Answer:

False

Number of literate males in age 20 – 30 = 600


Number of literate males in age 30 – 40 = 800


Number of literate males in age 40 – 50 = 500


⇒ Number of literate males in above age 20 = 600 + 800 + 500


⇒ Number of literate males in above age 20 = 1900


Hence, the statement is false.



Question 71.

In question, state whether the statements are true (T) or false (F).

The class size of the class interval m 60 – 68 is


Answer:

True

Class size of a class interval = Upper Limit – Lower Limit


⇒ Class size of the class interval 60 – 68 = 68 – 60


⇒ Class size of the class interval 60 – 68 = 8


Hence, the statement is true.



Question 72.

In question, state whether the statements are true (T) or false (F).

On throwing a dice once, the probability of occurence of an even number is 1/2.


Answer:

True

Even numbers on a dice are 2, 4 and 6


∴ Total number of even numbers = 3


⇒ Total number of favourable outcomes = 3


⇒ All Numbers on a dice = 6


⇒ Total number of outcomes = 6





Hence, the statement is true.



Question 73.

In question, state whether the statements are true (T) or false (F).

On throwing a dice once, the probability of occurence of a composite number is 1/2.


Answer:

False

Composite numbers on a dice are 4 and 6


∴ Total number of even numbers = 2


⇒ Total number of favourable outcomes = 2


⇒ All Numbers on a dice = 6


⇒ Total number of outcomes = 6





Hence, the statement is false.



Question 74.

In question, state whether the statements are true (T) or false (F).

From the given pie chart, we can infer that production of Manganese is least in state B.



Answer:

False

No we cannot infer, from the given pie chart that the production of Manganese is least in state B since we do not know the central angle of the sectors.


Hence, the statement is false.



Question 75.

In question, state whether the statements are true (T) or false (F).

One or more outcomes of an experiment make an event.


Answer:

True

An event is a set of outcomes of an experiment (a subset of the sample space) to which a probability is assigned.


Hence, the statement is true.



Question 76.

In question, state whether the statements are true (T) or false (F).

The probability of getting number 6 in a throw of a dice is 1/6. Similarly the probability of getting a number 5 is 1/5.


Answer:

False

Favourable outcome is 5


⇒ Total number of favourable outcomes =


⇒ All Numbers on a dice = 6


⇒ Total number of outcomes = 6




The probability of getting 5 is also .


Hence, the statement is false.



Question 77.

In question, state whether the statements are true (T) or false (F).

The probability of getting a prime number is the same as that of a composite number in a throw of a dice


Answer:

False

Prime numbers on a dice are 2, 3 and 5


⇒ Number of prime numbers on a dice = 3


⇒ Number of favourable outcomes for prime numbers = 3


Composite numbers on a dice are 4 and 4


⇒ Number of composite numbers on a dice = 2


⇒ Number of favourable outcomes for composite numbers = 2


Since the number of outcomes differs therefore probability would differ too.


Hence, the statement is false.



Question 78.

In question, state whether the statements are true (T) or false (F).

In a throw of a dice, the probability of getting an even number is the same as that of getting an odd number.


Answer:

True

Even numbers on a dice are 2, 4 and 6


⇒ Number of even numbers on a dice = 3


⇒ Number of favourable outcomes for even numbers = 3


Odd numbers on a dice are 1, 3 and 5


⇒ Number of odd numbers on a dice = 3


⇒ Number of favourable outcomes for odd numbers = 3


Since the number of outcomes is same therefore probability would be same too.


Hence, the statement is true.




Question 79.

In question, state whether the statements are true (T) or false (F).

To verify pythagoras theorem is a random experiment.


Answer:

False

In Pythagoras theorem, there can be only one result, therefore it is not a random experiment.


Hence, the statement is false.



Question 80.

In question, state whether the statements are true (T) or false (F).

The following pictorial representation of data is a histogram.



Answer:

True

A histogram is a display of statistical information that uses rectangles to show the frequency of data items in successive numerical intervals of equal size.


Yes, it is a histogram.


Hence, the statement is true.



Question 81.

Given below is a frequency distribution table. Read it and answer the questions that follow:



(a) What is the lower limit of the second-class interval?

(b) What is the upper limit of the last class interval?

(c) What is the frequency of the third class?

(d) Which interval has a frequency of 10?

(e) Which interval has the lowest frequency?

(f) What is the class size?


Answer:

(a) Second class interval is 20 – 30


⇒ Its lower limit = 20


(b) Last class interval is 50 – 60


⇒ Its upper limit = 60


(c) The third class is 30 – 40. Its frequency is 4.


(d) The interval that has a frequency of 10 is 20 – 30.


(e) The lowest frequency is 4 which corresponds to the interval 30 – 40.


(f) Class size = Upper Limit – Lower Limit


⇒ Class size is 10.



Question 82.

The top speeds of thirty different land animals have been organized into a frequency table. Draw a histogram for the given data.



Answer:

The histogram is-




Question 83.

Given below is a pie chart showing the time spend by a group of 350 children in different games. Observe it and answer the questions that follow.



(a) How many children spend at least one hour in playing games?

(b) How many children spend more than 2 hours in playing games?

(c) How many children spend 3 or lesser hours in playing games?

(d) Which is greater — number of children who spend 2 hours or more per day or number of children who play for less than one hour?


Answer:

(a) 6% children spend less 1 hour in playing games


Children who spend at least 2 hours = 100% – 6%


Children who spend at least 2 hours = 94%




⇒ No. of children spending atleast 2 hours = 329


(b) 34% children spend 3 hours in playing games


10% children spend 4 hours in playing games


4% children spend 5 hours in playing games


Total no. of children spending more than 2 hours = 34% + 10% + 4%


⇒ Total no. of children spending more than 2 hours = 48%




⇒ No. of children spending more than 2 hours = 168


(c) 6% children spend less than 1 hour in playing games


16% children spend 1 hour in playing games


30% children spend 2 hours in playing games


34% children spend 3 hours in playing games


Total no. of children spending 3 or lesser hours =


6% + 16% + 30% + 34%


⇒ Total no. of children spending 3 or lesser hours = 86%




⇒ No. of children spending 3 or lesser hours = 301


(d) No. of children who spent 2 hours or more = 30% + 34% + 10% + 4%


⇒ No. of children who spent 2 hours or more = 78%


And,


No. of children who spent less than 1 hour = 6%


Clearly,


No. of children who spent 2 hours or more is greater



Question 84.

The pie chart on the right shows the result of a survey carried out to find the modes of travel used by the children to go to school. Study the pie chart and answer the questions that follow.



(a) What is the most common mode of transport?

(b) What fraction of children travel by car?

(c) If 18 children travel by car, how many children took part in the survey?

(d) How many children use taxi to travel to school?

(e) By which two modes of transport are equal number of children travelling


Answer:

(a) Since, bus has the highest central angle i.e., 120°


Hence, the most common mode of transport is the bus.


(b)


(c)



⇒ Total no. of Children = 18 × 4


⇒ Total no. of Children = 72


(d) Central angle of students who do not take taxi = 120° + 90° + 60° + 60°


⇒ Central angle of students who do not take taxi = 330°


⇒ Central angle of students who take taxi = 360° – 330°


⇒ Central angle of students who take taxi = 30°




⇒ No. of Children travelling by taxi = 6


(e) Since, the central angle for students travelling by cycle and those who walk is same.


Hence, the two modes of transport are equal number of children travelling are Cycle and Walk.



Question 85.

A dice is rolled once. What is the probability that the number on top will be

(a) Odd

(b) Greater than 5

(c) A multiple of 3

(d) Less than 1

(e) A factor of 36

(f) A factor of 6


Answer:

False

(a) All odd numbers are 1, 3, 5


No. of odd numbers = 3


⇒ Total number of favourable outcomes = 3


⇒ All Numbers on a dice = 6


⇒ Total number of outcomes = 6




(b) Number greater than 5 is 6


No. of numbers greater than 5 = 1


⇒ Total number of favourable outcomes = 1


⇒ All Numbers on a dice = 6


⇒ Total number of outcomes = 6




(c) Multiples of 3 are 3 and 6


No. of Multiples of 3 = 2


⇒ Total number of favourable outcomes = 2


⇒ All Numbers on a dice = 6


⇒ Total number of outcomes = 6




(d) There is no number less than 1


Hence, probability of less than 1 = 0



(e) Factors of 36 are 1, 2, 3, 4 and 6


No. of Factors of 36 = 5


⇒ Total number of favourable outcomes = 5


⇒ All Numbers on a dice = 6


⇒ Total number of outcomes = 6




(f) Factors of 6 are 1, 2, 3 and 6


No. of Factors of 6 = 4


⇒ Total number of favourable outcomes = 4


⇒ All Numbers on a dice = 6


⇒ Total number of outcomes = 6





Question 86.

Classify the following statements under appropriate headings.

(a) Getting the sum of angles of a triangle as 180°.

(b) India winning a cricket match against Pakistan.

(c) Sun setting in the evening.

(d) Getting 7 when a die is thrown.

(e) Sun rising from the west.

(f) Winning a racing competition by you.


Answer:


(a) Since, the sum of angles of a triangle as 180° therefore, it is certain to happen.


(b) The result is unpredictable therefore, it may or may not happen


(c) Since, the sun always sets in the evening therefore, it is certain to happen.


(d) 7 is not an outcome when a dice is thrown therefore it is impossible to happen.


(e) Sun always rises from the east, therefore it is impossible to happen.


(f) The result is unpredictable therefore, it may or may not happen



Question 87.

Study the pie chart given below depicting the marks scored by a student in an examination out of 540. Find the marks obtained by him in each subject.


Answer:

Percentage of Hindi = 16.67%



⇒ Marks obtained in Hindi = 90.018 ~ 90


⇒ Marks obtained in Hindi = 90


Percentage of English = 25%



⇒ Marks obtained in English = 135


Percentage of Social Science = 5.55%



⇒ Marks obtained in Social Science = 29.97 ~ 30


⇒ Marks obtained in Social Science = 30


Percentage of Mathematics = 33.33%



⇒ Marks obtained in Mathematics = 179.98 ~ 180


⇒ Marks obtained in Mathematics = 180


Percentage of Science = 19.44%



⇒ Marks obtained in Science = 104.98 ~ 105


⇒ Marks obtained in Science = 105



Question 88.

Ritwik draws a ball from a bag that contains white and yellow balls. The probability of choosing a white ball is . If the total number of balls in the bag is 36, find the number of yellow balls.


Answer:




Now,




⇒ No. of yellow balls = 28



Question 89.

Look at the histogram below and answer the questions that follow.



(a) How many students have height more than or equal to 135 cm but less than 150 cm?

(b) Which class interval has the least number of students?

(c) What is the class size?

(d) How many students have height less than 140 cm?


Answer:

(a) Number of students who have height more than or equal to 135 cm but less than 150 cm = 14 + 18 + 10 = 42


(b) Class interval that has the least number of students = 150–155


(c) Class Size = Upper Limit – Lower Limit


⇒ Class Size = 130 – 125


⇒ Class Size = 5


(d) Students that have height less than 140 cm = 6 + 8 + 14 = 28



Question 90.

Following are the number of members in 25 families of a village:

6, 8, 7, 7, 6, 5, 3, 2, 5, 6, 8, 7, 7, 4, 3, 6, 6, 6, 7, 5, 4, 3, 3, 2, 5.

Prepare a frequency distribution table for the data using class intervals 0 –2, 2 –4, etc.


Answer:



Question 91.

Draw a histogram to represent the frequency distribution in question 91.


Answer:

The histogram is-




Question 92.

The marks obtained (out of 20) by 30 students of a class in a test are as follows:

14, 16, 15, 11, 15, 14, 13, 16, 8, 10, 7, 11, 18, 15, 14, 19, 20, 7, 10, 13, 12, 14, 15, 13, 16, 17, 14, 11, 10, 20.

Prepare a frequency distribution table for the above data using class intervals of equal width in which one class interval is 4 –8 (excluding 8 and including 4).


Answer:



Question 93.

Prepare a histogram from the frequency distribution table obtained in question 93.


Answer:

The histogram is-




Question 94.

The weights (in kg) of 30 students of a class are:

39, 38, 36, 38, 40, 42, 43, 44, 33, 33, 31, 45, 46, 38, 37, 31, 30, 39, 41, 41, 46, 36, 35, 34, 39, 43, 32, 37, 29, 26.

Prepare a frequency distribution table using one class interval as (30 – 35), 35 not included.

(i) Which class has the least frequency?

(ii) Which class has the maximum frequency?


Answer:


(i) The class that has the least frequency is 25 – 30.


(ii) The class that has the maximum frequency is 35 – 40.



Question 95.

Shoes of the following brands are sold in Nov. 2007 at a shoe store. Construct a pie chart for the data.



Answer:

Total no. of shoes = 130 + 120 + 90 + 40 + 20 = 400


Central angle for-









Question 96.

The following pie chart depicts the expenditure of a state government under different heads.

(i) If the total spending is 10 crores, how much money was spent on roads?

(ii) How many times is the amount of money spent on education compared to the amount spent on roads?

(iii) What fraction of the total expenditure is spent on both roads and public welfare together?



Answer:

(i)



⇒ Amount spent on roads = 1 crore


(ii)



⇒ Amount spent on education = 2.5 crore




⇒ Amount spent on roads = 1 crore


Now,




⇒ Amount spent on education = 2.5 × Amount spent on roads


(iii)







Question 97.

The following data represents the different number of animals in a zoo. Prepare a pie chart for the given data.



Answer:

Total no. of animals = 42 + 15 + 26 + 24 + 13 = 120


Central angle for-









Question 98.

Playing cards

(a) From a pack of cards the following cards are kept face down:



Suhail wins if he picks up a face card. Find the probability of Suhail winning?

(b) Now the following cards are added to the above cards:



What is the probability of Suhail winning now? Reshma wins if she picks up a 4. What is the probability of Reshma winning?

[Queen, King and Jack cards are called face cards.]


Answer:

(a) No. of face cards = 1


⇒ No. of favourable outcomes = 1


Total no. of cards = 7


⇒ No. of outcomes = 7




(b) No. of face cards = 4


⇒ No. of favourable outcomes = 4


Total no. of cards = 15


⇒ No. of outcomes = 15




No. of fours = 4


⇒ No. of favourable outcomes = 4


Total no. of cards = 15


⇒ No. of outcomes = 15





Question 99.

Construct a frequency distribution table for the following weights (in grams) of 35 mangoes, using the equal class intervals, one of them is 40 – 45 (45 not included).

30, 40, 45, 32, 43, 50, 55, 62, 70, 70, 61, 62, 53, 52, 50, 42, 35, 37, 53, 55, 65, 70, 73, 74, 45, 46, 58, 59, 60, 62, 74, 34, 35, 70, 68.

(a) How many classes are there in the frequency distribution table?

(b) Which weight group has the highest frequency?


Answer:


(i) Number of classes = 9


(ii) The class that has the highest frequency is 70 – 75.



Question 100.

Complete the following table:



Find the total number of persons whose weights are given in the above table.


Answer:


Total number of persons = 35



Question 101.

Draw a histogram for the following data.



Answer:



Question 102.

In a hypothetical sample of 20 people, the amount of money (in thousands of rupees) with each was found to be as follows:

114, 108, 100, 98, 101, 109, 117, 119, 126, 131, 136, 143, 156, 169, 182, 195, 207, 219, 235, 118.

Draw a histogram of the frequency distribution, taking one of the class intervals as 50 –100.


Answer:

The frequency distribution table is given below:



The histogram is given below:




Question 103.

The below histogram shows the number of literate females in the age group of 10 to 40 years in a town.

(a) Write the classes assuming all the classes are of equal width.

(b) What is the classes width?

(c) In which age group are literate females the least?

(d) In which age group is the number of literate females the highest?



Answer:

(a) Age group is 10 – 40 year


Therefore, dividing it in 7 classes of equal class intervals are,


10 – 15, 15 – 20, 20 – 25, 25 – 30, 30 – 35, 35 – 40 and 40 – 45


(b) Class Width = Upper Limit – Lower Limit


⇒ Class Width = 15 – 10


⇒ Class Width = 5


(c) Literal females are least in 10 – 15


(d) Literal females are highest in 15 – 20



Question 104.

The following histogram shows the frequency distribution of teaching experiences of 30 teachers in various schools:



(a) What is the class width?

(b) How many teachers are having the maximum teaching experience and how many have the least teaching experience?

(c) How many teachers have teaching experience of 10 to 20 years?


Answer:

(a) Answer: From the above histogram, we can say that the 5.


(b) From the diagram, 16 teachers have the maximum teaching experience i.e. of 15 years.


And, 2 teachers have the least experience (< 5 years)


(c) Form the chart,


16 teachers have the experience between 10 years to 20 years.



Question 105.

In a district, the number of branches of different banks is given below:



Draw a pie chart for this data.


Answer:

Total no. of branches = 30 + 17 + 15 + 10 = 72


Central angle for-








Question 106.

For the development of basic infrastructure in a district, a project of Rs 108 crore approved by Development Bank is as follows:



Draw a pie chart for this data.


Answer:

Total amount = 43.2 + 16.2 + 27 + 21.6 = 108


Central angle for-








Question 107.

In the time table of a school, periods allotted per week to different teaching subjects are given below:



Draw a pie chart for this data.


Answer:

Total no. of periods = 7 + 8 + 8 + 8 + 7 + 4 + 3 = 45


Central angle for-











Question 108.

A survey was carried out to find the favourite beverage preferred by a certain group of young people. The following pie chart shows the findings of this survey.

From this pie chart answer the following:

(i) Which type of beverage is liked by the maximum number of people.

(ii) If 45 people like tea, how many people were surveyed?



Answer:

(i) Coldrinks are liked by maximum number of people, since it has highest percentage.


(ii) Number of people that liked tea = 45


Percentage of people that liked tea = 15%





⇒ Total number of people = 300



Question 109.

The following data represents the approximate percentage of water in various oceans. Prepare a pie chart for the given data.

Pacific 40%

Atlantic 30%

Indian 20%

Others 10%


Answer:

Total amount = 40 + 30 + 20 + 10 = 100


Central angle for-








Question 110.

At a Birthday Party, the children spin a wheel to get a gift. Find the probability of

(a) getting a ball

(b) getting a toy car

(c) any toy except a chocolate



Answer:

Total no. of events = 8


(i) No. of events of getting a ball = 2




(ii) No. of events of getting a toy car = 3




(iii) No. of events of getting any toy except chocolate = 7





Question 111.

Sonia picks up a card from the given cards.



Calculate the probability of getting

(a) an odd number

(b) a Y card

(c) a G card

(d) B card bearing number > 7


Answer:

Total no. of events = 10


(i) No. of events of an odd no = 5





(ii) No. of events of Y card = 3




(iii) No. of events of G card = 2





(iv) No. of events of getting B card bearing number > 7 = 7






Question 112.

Identify which symbol should appear in each sector in.



Answer:

Total Quantity = 800 + 700 + 550 + 450


⇒ Total Quantity = 2500



Thus, the first symbol has 32%



Thus, the second symbol has 28%



Thus, the third symbol has 22%



Thus, the fourth symbol has 18%



Question 113.

Identify which symbol should appear in each sector.



Answer:

Total Quantity = 192 + 228 + 180


⇒ Total Quantity = 600



Thus, yellow colour is 38%



Thus, red colour is 32%



Thus, pink colour is 30%



Question 114.

A financial counselor gave a client this pie chart describing how to budget his income. If the client brings home Rs. 50,000 each month, how much should he spend in each category?



Answer:

Monthly income = 50000


Money Spent-










Question 115.

Following is a pie chart showing the amount spent in rupees (in thousands) by a company on various modes of advertising for a product. Now answer the following questions.

1. Which type of media advertising is the greatest amount of the total?

2. Which type of media advertising is the least amount of the total?

3. What per cent of the total advertising amount is spent on direct mail campaigns?

4. What per cent of the advertising amount is spent on newspaper and magazine advertisements?

5. What media types do you think are included in miscellaneous? Why aren’t those media types given their own category?



Answer:

1. The greatest amount of total is spent in Newspapers.

2. The greatest amount of total is spent in Radio.


3. Total = 40 + 42 + 23 + 7 + 11 + 39 + 14 + 15 + 9 = 200



% Spent in direct mail = 19.5


4. Total = 40 + 42 + 23 + 7 + 11 + 39 + 14 + 15 + 9 = 200


Newspaper + Magazine = 42 + 23 = 65



% Spent in Newspaper and Magazine = 32.5


5. The various media types on which not much amount is spent must be included in Miscellaneous



Question 116.

In question, state whether the statements are true (T) or false (F).

If a pair of coins is tossed, then the number of outcomes is 2.


Answer:

False

When two coins are tossed the outcomes are,


HH, HT, TH, TT


Therefore, number of outcomes are 4.


Hence, the statement is false.