EduSahara™ Worksheet

Question 1

1.

Two coins are tossed simultaneously 70 times and it was observed that both heads appeared 45 times. If two coins are tossed simultaneously at random, what is the probability of getting both heads?

(i)

5
14
(ii)

9
14
(iii)

2
3
(iv)

4
7
(v)

5
7

Question 2

2.

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

(i)

11
36
(ii)

25
36
(iii)

1
3
(iv)

12
37
(v)

5
18

Question 3

3.

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
13
(ii)

1
26
(iii)

1
52
(iv)

1
4
(v)

3
13

Question 4

4.

A bag contains 42 gray marbles, 6 yellow marbles, 9 blue marbles and 3 pink marbles. One marble is drawn at random from the bag. Find the probability that the marble drawn is neither gray nor yellow.

(i)

1
5
(ii)

0
(iii)

1
3
(iv)

2
5
(v)

4
5

Question 5

5.

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

(i)

49
(ii)

54
(iii)

52
(iv)

51
(v)

53

Question 6

6.

Two unbiased coins are tossed simultaneously. Find the probability of getting at least two heads.

(i)

0
(ii)

2
5
(iii)

3
4
(iv)

1
4
(v)

1
2

Question 7

7.

An unbiased die is thrown once. Find the probability of getting a number less than 4?

(i)

5
6
(ii)

2
3
(iii)

1
2
(iv)

4
5
(v)

3
4

Question 8

8.

One card is drawn at random from a well shuffled deck of 52 cards. What is the probability that the card drawn is '2' of hearts?

(i)

3
13
(ii)

1
4
(iii)

1
13
(iv)

1
26
(v)

1
52

Question 9

9.

An unbiased die is thrown once. Find the probability of getting a number between 3 and 5?

(i)

5
6
(ii)

1
3
(iii)

0
(iv)

1
6
(v)

2
7

Question 10

10.

An unbiased die is thrown once. Find the probability of getting a 6?

(i)

5
6
(ii)

2
7
(iii)

0
(iv)

1
3
(v)

1
6

Question 11

11.

Which of the following experiments have equally likely outcomes?

a)	A baby is born. It is a boy or girl
b)	A ball is hit. It reaches the boundary or not
c)	A man starts his vehicle. It starts or it does not starts
d)	A man throws a die. The number on the top is either 2 or not 2
e)	A true/false question is attempted. The answer is either right or wrong

(i)

{d,b,a}
(ii)

{a,e}
(iii)

{c,e,a}
(iv)

{c,e}
(v)

{b,a}

Question 12

12.

On a particular day, at a crossing in a city, the various types of 130 vehicles going past during a time-interval were observed as under:

Type of Vehicle

Four-wheeler

Three-wheeler

Two-wheeler

Frequency

25

50

55

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

(i)

5
13
(ii)

11
26
(iii)

15
26
(iv)

6
13
(v)

4
9

Question 13

13.

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

(i)

2
7
(ii)

1
3
(iii)

0
(iv)

1
6
(v)

5
6

Question 14

14.

270 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

81

90

99

Compute the probability of the family, chosen at random, having no girls.

(i)

7
10
(ii)

4
11
(iii)

3
10
(iv)

2
5
(v)

1
5

Question 15

15.

Three coins are tossed simultaneously 175 times with the following frequencies of different outcomes :

Outcome

3 heads

2 heads

1 heads

No heads

Frequency

25

40

50

60

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

(i)

13
36
(ii)

12
35
(iii)

11
35
(iv)

13
35
(v)

23
35

Question 16

16.

55 cards are numbered 1,2,3,....55 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)

4
5
(ii)

1
5
(iii)

0
(iv)

1
3
(v)

2
5

Question 17

17.

Which of the following are possible values of probability?

a)

3

b)

0.56

c)

5

6

d)

5

2

e)

-4

(i)

{e,a,b}
(ii)

{a,b}
(iii)

{d,c}
(iv)

{d,c,b}
(v)

{b,c}

Question 18

18.

A lot of 25 bulbs contain 18 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)

2
5
(iii)

0
(iv)

1
4
(v)

3
4

Question 19

19.

A carton consist of 68 shirts of which 53 are good, 10 have minor defects and 5 have major defects. Kavish, a trader, will only accept the shirts which are good, but Aruna, 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 Aruna?

(i)

63
68
(ii)

16
17
(iii)

31
34
(iv)

64
69
(v)

5
68

Question 20

20.

A coin is tossed 70 times and head appears 30 times. If the coin is tossed again, what is the probability of getting a tail?

(i)

3
7
(ii)

4
7
(iii)

5
7
(iv)

5
8

Question 21

21.

89 cards are numbered 1,2,3,....89 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)

44
89
(ii)

23
45
(iii)

45
89
(iv)

46
89

Question 22

22.

A lot of 25 bulbs contain 4 defective ones. One bulb is drawn at random from the lot. What is the probability that this bulb is defective ?

(i)

5
26
(ii)

4
25
(iii)

1
5
(iv)

3
25
(v)

21
25

Question 23

23.

A bag contains 56 red balls, 36 gray balls, 44 black balls and 48 blue balls. One ball is drawn at random from the bag. Find the probability that the ball drawn is not black.

(i)

36
47
(ii)

18
23
(iii)

17
23
(iv)

35
46
(v)

11
46

Question 24

24.

When two dice are thrown simultaneously, how many elementary events are possible?

(i)

35
(ii)

37
(iii)

36
(iv)

33
(v)

39

Question 25

25.

Which of the following are true?

a)	The probability of an impossible event is 1
b)	For an event E, we have 0 ≤ P(E) ≤ 1
c)	The probability of an imposible event can be > 1
d)	The probability of a sure event is 1
e)	The probability of an unsure event is 0

(i)

{e,a,b}
(ii)

{c,d}
(iii)

{b,d}
(iv)

{c,d,b}
(v)

{a,b}

Assignment Key