EduSahara™ Worksheet

Question 1

1.

A coin is tossed 60 times and head appears 50 times. If the coin is tossed again, what is the probability of getting a tail?

(i)

1
6
(ii)

2
7
(iii)

1
3
(iv)

0
(v)

5
6

Question 2

2.

A lot of 22 bulbs contain 7 defective ones. One bulb is drawn at random from the lot. What is the probability that this bulb is defective ?

(i)

3
11
(ii)

7
22
(iii)

15
22
(iv)

4
11
(v)

8
23

Question 3

3.

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

(i)

2
3
(ii)

5
6
(iii)

4
5
(iv)

1
2
(v)

3
4

Question 4

4.

Two coins are tossed simultaneously 150 times and it was observed that both heads appeared 75 times. If two coins are tossed simultaneously at random, what is the probability of getting both heads?

(i)

4
5
(ii)

2
3
(iii)

3
4
(iv)

5
6
(v)

1
2

Question 5

5.

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 14.00 cm?

(i)

155
667
(ii)

153
667
(iii)

513
667
(iv)

155
668
(v)

154
667

Question 6

6.

Three unbiased coins are tossed simultaneously. Find the probability of getting no head.

(i)

2
9
(ii)

0
(iii)

1
8
(iv)

7
8
(v)

1
4

Question 7

7.

A coin is tossed 80 times and tail appears 65 times. If the coin is tossed again, what is the probability of getting a head?

(i)

1
8
(ii)

4
17
(iii)

13
16
(iv)

3
16
(v)

1
4

Question 8

8.

When a card is selected randomly out of a pack of cards, how many elementary events are possible?

(i)

49
(ii)

53
(iii)

52
(iv)

55
(v)

51

Question 9

9.

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

(i)

2
7
(ii)

0
(iii)

1
3
(iv)

5
6
(v)

1
6

Question 10

10.

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

(i)

5
8
(ii)

4
9
(iii)

3
8
(iv)

1
2
(v)

1
4

Question 11

11.

A bag contains 6 black balls, 18 yellow balls, 3 blue balls and 45 white balls. One ball is drawn at random from the bag. Find the probability that the ball drawn is neither black nor white.

(i)

7
24
(ii)

8
25
(iii)

17
24
(iv)

1
4
(v)

1
3

Question 12

12.

A bag contains 55 gray marbles, 5 pink marbles, 65 blue marbles and 70 black marbles. One marble is drawn at random from the bag. Find the probability that the marble drawn is black.

(i)

25
39
(ii)

5
13
(iii)

3
8
(iv)

1
3
(v)

14
39

Question 13

13.

Two unbiased coins are tossed simultaneously. Find the probability of getting no head.

(i)

0
(ii)

3
4
(iii)

2
5
(iv)

1
4
(v)

1
2

Question 14

14.

A die is thrown twice. What is the probability that 3 will not come up either time?

(i)

26
37
(ii)

11
36
(iii)

13
18
(iv)

25
36
(v)

2
3

Question 15

15.

87 cards are numbered 1,2,3,....87 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)

23
87
(ii)

64
87
(iii)

22
87
(iv)

8
29
(v)

3
11

Question 16

16.

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

10

8

13

14

13

18

16

6

27

What is the empirical probability that an engineer lives greater than 27 km from her place of work?

(i)

0
(ii)

1
4
(iii)

1
(iv)

3
4
(v)

1
2

Question 17

17.

When two coins are tossed simultaneously, how many elementary events are possible?

(i)

1
(ii)

6
(iii)

3
(iv)

4
(v)

5

Question 18

18.

Which of the following experiments have equally likely outcomes?

a)	A man throws a die. The number on the top is either 6 or not 6
b)	A true/false question is attempted. The answer is either right or wrong
c)	A baby is born. It is a boy or girl
d)	A ball is hit. It reaches the boundary or not
e)	A man starts his vehicle. It starts or it does not starts

(i)

{b,c}
(ii)

{e,a,b}
(iii)

{d,c,b}
(iv)

{d,c}
(v)

{a,b}

Question 19

19.

71 cards are numbered 1,2,3,....71 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)

14
71
(ii)

13
71
(iii)

15
71
(iv)

57
71
(v)

5
24

Question 20

20.

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

(i)

4
5
(ii)

3
4
(iii)

1
2
(iv)

1
4
(v)

1

Question 21

21.

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

(i)

1
2
(ii)

4
5
(iii)

1
(iv)

3
4
(v)

1
4

Question 22

22.

Which of the following are possible values of probability?

a)

-5.1

b)

1

3

c)

4

d)

0.6

e)

7

6

(i)

{a,b}
(ii)

{c,d,b}
(iii)

{b,d}
(iv)

{c,d}
(v)

{e,a,b}

Question 23

23.

Three coins are tossed simultaneously 325 times with the following frequencies of different outcomes :

Outcome

3 heads

2 heads

1 heads

No heads

Frequency

40

80

100

105

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

(i)

1
3
(ii)

21
65
(iii)

22
65
(iv)

44
65
(v)

4
13

Question 24

24.

Two unbiased dice are thrown simultaneously. Find the probability of getting 10 as the sum of the two numbers on the dice.

(i)

1
6
(ii)

2
13
(iii)

11
12
(iv)

1
12
(v)

0

Question 25

25.

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

Blood group

A

AB

B

O

Number of students

54

72

81

90

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

(i)

7
33
(ii)

25
33
(iii)

8
33
(iv)

3
11
(v)

9
34

Assignment Key