EduSahara™ Worksheet

Question 1

1.

A die is thrown twice. What is the probability that 2 will come up atleast once?

(i)

5
18
(ii)

11
36
(iii)

25
36
(iv)

1
3
(v)

12
37

Question 2

2.

A lot of 33 bulbs contain 15 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)

1
2
(ii)

9
16
(iii)

15
32
(iv)

17
32
(v)

6
11

Question 3

3.

A single unbiased coin is tossed. Find the probability of getting a head.

(i)

5
6
(ii)

2
3
(iii)

3
4
(iv)

4
5
(v)

1
2

Question 4

4.

Two unbiased coins are tossed simultaneously. Find the probability of getting at least one head.

(i)

4
5
(ii)

3
4
(iii)

1
4
(iv)

1
2
(v)

1

Question 5

5.

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

40

55

If the three coins are simultaneously tossed again, compute the probability of '1 heads' coming up.

(i)

23
31
(ii)

7
31
(iii)

9
32
(iv)

9
31
(v)

8
31

Question 6

6.

A lot of 35 bulbs contain 13 defective ones. One bulb is drawn at random from the lot. What is the probability that this bulb is defective ?

(i)

13
35
(ii)

12
35
(iii)

7
18
(iv)

2
5
(v)

22
35

Question 7

7.

An unbiased die is thrown once. Find the probability of getting an even number?

(i)

2
3
(ii)

4
5
(iii)

3
4
(iv)

1
2
(v)

5
6

Question 8

8.

If P(E) =
0.71
, find P(
E
)

(i)

7.29
(ii)

8.29
(iii)

1.29
(iv)

0.29
(v)

2.29

Question 9

9.

Two unbiased dice are thrown simultaneously. Find the probability of getting a doublet.

(i)

2
7
(ii)

0
(iii)

5
6
(iv)

1
6
(v)

1
3

Question 10

10.

A die is thrown 450 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

45

65

95

105

110

30

If the die is thrown again randomly, find the probability of getting 4 as outcome.

(i)

7
30
(ii)

1
5
(iii)

23
30
(iv)

4
15
(v)

8
31

Question 11

11.

Three unbiased coins are tossed simultaneously. Find the probability of getting exactly one head.

(i)

3
8
(ii)

4
9
(iii)

1
4
(iv)

1
2
(v)

5
8

Question 12

12.

98 cards are numbered 1,2,3,....98 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)

73
98
(ii)

26
99
(iii)

12
49
(iv)

25
98
(v)

13
49

Question 13

13.

One card is drawn at random from a well shuffled deck of 52 cards. What is the probability that the card drawn is a black king?

(i)

1
4
(ii)

1
26
(iii)

3
13
(iv)

1
52
(v)

1
13

Question 14

14.

A bag contains 18 orange marbles, 33 white marbles, 3 black marbles and 18 gray marbles. One marble is drawn at random from the bag. Find the probability that the marble drawn is black or gray.

(i)

17
24
(ii)

8
25
(iii)

7
24
(iv)

1
4
(v)

1
3

Question 15

15.

Two unbiased coins are tossed simultaneously. Find the probability of getting exactly one head.

(i)

3
4
(ii)

4
5
(iii)

5
6
(iv)

2
3
(v)

1
2

Question 16

16.

Two players Simran and Aparna play a tennis match. It is known that the probability of Simran winning the match is 0.67. What is the probability of Aparna winning the match?

(i)

67
100
(ii)

17
50
(iii)

34
101
(iv)

8
25
(v)

33
100

Question 17

17.

An unbiased die is thrown once. Find the probability of getting a number greater than 5?

(i)

5
6
(ii)

1
3
(iii)

0
(iv)

1
6
(v)

2
7

Question 18

18.

The following table shows the blood-groups of 297 students of a class.

Blood group

A

O

AB

B

Number of students

45

54

90

108

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

(i)

3
11
(ii)

9
11
(iii)

1
4
(iv)

2
11
(v)

1
11

Question 19

19.

Which of the following are true?

a)

P(E) + P(not E) = 1

b)

P(E) = 1 - P(
E
)

c)

P(E) + P(
E
) = 0

d)

P(E) - P(not E) = 0

e)

P(E) - P(
E
) = 0

(i)

{d,b,a}
(ii)

{d,b}
(iii)

{a,b}
(iv)

{c,a}
(v)

{e,c,a}

Question 20

20.

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 greater then 28?

(i)

33
61
(ii)

17
31
(iii)

32
61
(iv)

28
61
(v)

34
61

Question 21

21.

Three unbiased coins are tossed simultaneously. Find the probability of getting at most one head.

(i)

5
6
(ii)

4
5
(iii)

1
2
(iv)

3
4
(v)

2
3

Question 22

22.

Which of the following experiments have equally likely outcomes?

a)	A man starts his vehicle. It starts or it does not starts
b)	A ball is hit. It reaches the boundary or not
c)	A true/false question is attempted. The answer is either right or wrong
d)	A man throws a die. The number on the top is either 5 or not 5
e)	A baby is born. It is a boy or girl

(i)

{a,c}
(ii)

{b,e}
(iii)

{b,e,c}
(iv)

{d,a,c}
(v)

{c,e}

Question 23

23.

A carton consist of 92 shirts of which 81 are good, 9 have minor defects and 2 have major defects. Daniel, a trader, will only accept the shirts which are good, but Kareena, 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 Kareena?

(i)

45
46
(ii)

1
46
(iii)

22
23
(iv)

46
47
(v)

1

Question 24

24.

One card is drawn at random from a well shuffled deck of 52 cards. What is the probability that the card drawn is a clubs?

(i)

1
52
(ii)

3
13
(iii)

1
4
(iv)

1
26
(v)

1
13

Question 25

25.

Two unbiased dice are thrown simultaneously. Find the probability of getting at least 5 as the sum of the two numbers on the dice.

(i)

1
6
(ii)

1
(iii)

2
3
(iv)

6
7
(v)

5
6

Assignment Key