EduSahara™ Worksheet

Question 1

1.

A survey of 150 men showed that only 75 of them know Hindi. Out of these men, if one is selected at random, what is the probability that the selected man knows Hindi?

(i)

5
6
(ii)

1
2
(iii)

4
5
(iv)

3
4
(v)

2
3

Question 2

2.

On a particular day, at a crossing in a city, the various types of 90 vehicles going past during a time-interval were observed as under:

Type of Vehicle

Four-wheeler

Three-wheeler

Two-wheeler

Frequency

25

30

35

Out of these vehicles, if one is choosen at random, what is the probability that the choosen vehicle is a 'Two-wheeler' ?

(i)

1
3
(ii)

8
19
(iii)

11
18
(iv)

7
18
(v)

4
9

Question 3

3.

The following table shows the blood-groups of 288 students of a class.

Blood group

B

AB

A

O

Number of students

45

72

81

90

One student of the class is choosen at random. What is the probability that the choosen student has blood group 'O' ?

(i)

1
4
(ii)

6
17
(iii)

5
16
(iv)

3
8
(v)

11
16

Question 4

4.

A bag contains 15 gray marbles, 3 white marbles, 39 blue marbles and 30 yellow marbles. One marble is drawn at random from the bag. Find the probability that the marble drawn is gray.

(i)

5
29
(ii)

6
29
(iii)

24
29
(iv)

1
5
(v)

4
29

Question 5

5.

A bag contains 60 red balls, 56 yellow balls, 8 gray balls and 20 pink balls. One ball is drawn at random from the bag. Find the probability that the ball drawn is not gray.

(i)

18
19
(ii)

1
18
(iii)

1
(iv)

17
18
(v)

8
9

Question 6

6.

A box contains 2 gray balls, 14 red balls, 18 orange balls and 30 black balls. One ball is drawn at random from the box. Find the probability that the ball drawn is gray or orange.

(i)

1
4
(ii)

11
16
(iii)

5
16
(iv)

6
17
(v)

3
8

Question 7

7.

A bag contains 6 orange marbles, 45 gray marbles, 36 pink marbles and 45 blue marbles. One marble is drawn at random from the bag. Find the probability that the marble drawn is neither orange nor blue.

(i)

7
11
(ii)

27
44
(iii)

13
22
(iv)

17
44
(v)

28
45

Question 8

8.

There are 52 students in a class room of whom 30 are boys and 22 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a boy ?

(i)

11
26
(ii)

15
26
(iii)

7
13
(iv)

16
27
(v)

8
13

Question 9

9.

There are 48 students in a class room of whom 20 are boys and 28 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a girl ?

(i)

1
2
(ii)

5
12
(iii)

2
3
(iv)

8
13
(v)

7
12

Question 10

10.

In a lottery, there are 24 prizes and 16 blanks. What is the probability of getting a prize?

(i)

3
5
(ii)

4
5
(iii)

2
5
(iv)

2
3

Question 11

11.

In a lottery, there are 27 prizes and 19 blanks. What is the probability of not getting a prize?

(i)

9
23
(ii)

19
46
(iii)

27
46
(iv)

10
23
(v)

20
47

Question 12

12.

Two players Soundarya and Revathi play a tennis match. It is known that the probability of Soundarya winning the match is 0.43. What is the probability of Revathi winning the match?

(i)

57
100
(ii)

14
25
(iii)

58
101
(iv)

43
100
(v)

29
50

Question 13

13.

162 families with 2 children were selected randomly, and the following data were recorded

No. of girls in a family

0

1

2

Number of families

45

54

63

Compute the probability of the family, chosen at random, having 1 girl.

(i)

1
2
(ii)

1
3
(iii)

0
(iv)

2
3

Question 14

14.

Three coins are tossed simultaneously 155 times with the following frequencies of different outcomes :

Outcome

3 heads

2 heads

1 heads

No heads

Frequency

25

35

45

50

If the three coins are simultaneously tossed again, compute the probability of 'No heads' coming up.

(i)

10
31
(ii)

21
31
(iii)

9
31
(iv)

11
31
(v)

11
32

Question 15

15.

A die is thrown 505 times with the frequencies for outcomes 1, 2, 3, 4, 5 and 6 as given in the following table

Outcome

1

2

3

4

5

6

Frequency

55

65

75

95

105

110

If the die is thrown again randomly, find the probability of getting 5 as outcome.

(i)

20
101
(ii)

21
101
(iii)

11
51
(iv)

22
101
(v)

80
101

Question 16

16.

The distances (in km) of engineers from their residence to their place of work were found as follows

30

26

18

13

5

9

6

15

13

What is the empirical probability that an engineer lives less than 9 km from her place of work?

(i)

7
9
(ii)

1
9
(iii)

1
3
(iv)

2
9
(v)

3
10

Question 17

17.

The distances (in km) of engineers from their residence to their place of work were found as follows

30

9

6

29

23

2

27

12

26

25

What is the empirical probability that an engineer lives greater than 26 km from her place of work?

(i)

3
10
(ii)

1
5
(iii)

2
5
(iv)

4
11
(v)

7
10

Question 18

18.

Sujatha and Swetha are friends. What is the probability that both will have different birthdays? (ignoring a leap year).

(i)

364
365
(ii)

363
365
(iii)

1
(iv)

365
366
(v)

1
365

Question 19

19.

Sowjanya and Rizvana are friends. What is the probability that both will have same birthdays? (ignoring a leap year).

(i)

0
(ii)

2
365
(iii)

1
183
(iv)

1
365
(v)

364
365

Question 20

20.

In a musical chair game, the person playing the music has been advised to stop playing the music at any time with in 2 minutes after she starts playing. What is the probabilty that the music will stop within the first half-minute after starting?

(i)

3
4
(ii)

0
(iii)

1
4
(iv)

1
2
(v)

2
5

Question 21

21.

A carton consist of 64 shirts of which 50 are good, 12 have minor defects and 2 have major defects. Vinay, a trader, will only accept the shirts which are good, but Simran, another trader, will only reject the shirts which have major defects. One shirt is drawn at random from the carton. What is the probability that it is acceptable to Vinay?

(i)

25
32
(ii)

26
33
(iii)

7
32
(iv)

13
16
(v)

3
4

Question 22

22.

A carton consist of 60 shirts of which 51 are good, 6 have minor defects and 3 have major defects. Naveen, a trader, will only accept the shirts which are good, but Fathima, another trader, will only reject the shirts which have major defects. One shirt is drawn at random from the carton. What is the probability that it is acceptable to Fathima?

(i)

1
(ii)

9
10
(iii)

1
20
(iv)

19
20
(v)

20
21

Question 23

23.

A lot of 21 bulbs contain 3 defective ones. One bulb is drawn at random from the lot. What is the probability that this bulb is defective ?

(i)

0
(ii)

2
7
(iii)

1
7
(iv)

1
4
(v)

6
7

Question 24

24.

A lot of 23 bulbs contain 17 defective ones. One bulb is drawn at random from the lot. Suppose the bulb drawn is not defective and is not replaced. Now one bulb is drawn at random from the rest. What is the probability that this bulb is not defective ?

(i)

2
11
(ii)

6
23
(iii)

17
22
(iv)

3
11
(v)

5
22

Question 25

25.

A box contains 20 discs which are numbered from 1 to 20. If one disc is drawn at random from the box, find the probability that it bears a two-digit number.

(i)

3
5
(ii)

9
20
(iii)

1
2
(iv)

4
7
(v)

11
20

Question 26

26.

A box contains 60 discs which are numbered from 1 to 60. If one disc is drawn at random from the box, find the probability that it bears a perfect square number.

(i)

1
10
(ii)

2
15
(iii)

8
61
(iv)

53
60
(v)

7
60

Question 27

27.

A box contains 30 discs which are numbered from 1 to 30. If one disc is drawn at random from the box, find the probability that it bears a number divisible by 5.

(i)

1
3
(ii)

0
(iii)

4
5
(iv)

1
5
(v)

2
5

Question 28

28.

A game consists of tossing a coin 3 times and noting its outcome each time. Srinivas wins if all the tosses give the same result i.e., three heads or three tails, and loses otherwise. Calculate the probability that Srinivas will lose the game.

(i)

1
4
(ii)

1
2
(iii)

1
(iv)

4
5
(v)

3
4

Question 29

29.

60 cards are numbered 1,2,3,....60 and put in a box and mixed thoroughly. A card is drawn at random. What is the probability that the number on the drawn card is an odd number?

(i)

3
4
(ii)

2
3
(iii)

1
2
(iv)

5
6
(v)

4
5

Question 30

30.

85 cards are numbered 1,2,3,....85 and put in a box and mixed thoroughly. A card is drawn at random. What is the probability that the number on the drawn card is a prime number?

(i)

24
85
(ii)

12
43
(iii)

62
85
(iv)

23
85
(v)

22
85

Question 31

31.

62 cards are numbered 1,2,3,....62 and put in a box and mixed thoroughly. A card is drawn at random. What is the probability that the number on the drawn card is divisible by 5?

(i)

6
31
(ii)

7
31
(iii)

5
31
(iv)

7
32
(v)

25
31

Question 32

32.

61 cards are numbered 1,2,3,....61 and put in a box and mixed thoroughly. A card is drawn at random. What is the probability that the number on the drawn card is less then 19?

(i)

19
61
(ii)

18
61
(iii)

17
61
(iv)

43
61
(v)

19
62

Question 33

33.

79 cards are numbered 1,2,3,....79 and put in a box and mixed thoroughly. A card is drawn at random. What is the probability that the number on the drawn card is greater then 26?

(i)

26
79
(ii)

53
79
(iii)

52
79
(iv)

54
79
(v)

27
40

Question 34

34.

Suppose a die is thrown on a rectangular region as shown below. What is the probability that it will land inside the circle of diameter 16.00 cm?

(i)

111
175
(ii)

64
175
(iii)

13
35
(iv)

9
25
(v)

65
176

Question 35

35.

A missing helicopter is reported to have crashed somewhere in the rectangular region shown in fig. What is the probability that it crashed inside the shaded region as shown in the figure?

(i)

1
8
(ii)

0
(iii)

1
4
(iv)

7
8
(v)

2
9

Assignment Key