EduSahara™ Worksheet

Question 1

1.

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

(i)

4
5
(ii)

1
2
(iii)

3
4
(iv)

5
6
(v)

2
3

Question 2

2.

A die is thrown 140 times. Prime numbers appeared on the upper face 75 times. If a die is thrown at random, what is the probability of getting a prime number?

(i)

1
2
(ii)

16
29
(iii)

13
28
(iv)

4
7
(v)

15
28

Question 3

3.

A lot of 36 bulbs contain 12 defective ones. One bulb is drawn at random from the lot. What is the probability that this bulb is defective ?

(i)

1
3
(ii)

0
(iii)

1
2
(iv)

2
3

Question 4

4.

If P(E) =
0.33
, find P(
E
)

(i)

1.67
(ii)

0.67
(iii)

2.67
(iv)

7.67
(v)

8.67

Question 5

5.

A die is thrown 475 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

35

70

75

90

100

105

If the die is thrown again randomly, find the probability of getting 2 as outcome.

(i)

3
19
(ii)

13
95
(iii)

14
95
(iv)

81
95
(v)

5
32

Question 6

6.

What is the probability of a sure event?

(i)

1
(ii)

0
(iii)

1
4
(iv)

1
2
(v)

3
4

Question 7

7.

There are 44 students in a class room of whom 22 are boys and 22 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a girl ?

(i)

4
5
(ii)

5
6
(iii)

3
4
(iv)

1
2
(v)

2
3

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 black suit ?

(i)

1
13
(ii)

1
4
(iii)

1
52
(iv)

1
26
(v)

3
13

Question 9

9.

Which of the following are true?

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

(i)

{c,d,b}
(ii)

{b,d}
(iii)

{a,b}
(iv)

{c,d}
(v)

{e,a,b}

Question 10

10.

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

(i)

3
4
(ii)

0
(iii)

2
5
(iv)

1
2
(v)

1
4

Question 11

11.

Three coins are tossed simultaneously 205 times with the following frequencies of different outcomes :

Outcome

3 heads

2 heads

1 heads

No heads

Frequency

40

50

55

60

If the three coins are simultaneously tossed again, compute the probability of '2 heads' coming up.

(i)

9
41
(ii)

10
41
(iii)

11
41
(iv)

11
42
(v)

31
41

Question 12

12.

An unbiased die is thrown once. Find the probability of getting a number between 2 and 6?

(i)

3
4
(ii)

4
5
(iii)

2
3
(iv)

1
2
(v)

5
6

Question 13

13.

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

(i)

4
5
(ii)

1
4
(iii)

1
(iv)

1
2
(v)

3
4

Question 14

14.

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

(i)

8
9
(ii)

7
8
(iii)

3
4
(iv)

1
(v)

1
8

Question 15

15.

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

(i)

1
4
(ii)

1
2
(iii)

3
8
(iv)

5
8
(v)

4
9

Question 16

16.

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

(i)

1
2
(ii)

5
6
(iii)

2
3
(iv)

3
4
(v)

4
5

Question 17

17.

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 24?

(i)

24
61
(ii)

19
31
(iii)

36
61
(iv)

37
61
(v)

38
61

Question 18

18.

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 12.00 cm?

(i)

397
1547
(ii)

397
1548
(iii)

1151
1547
(iv)

395
1547
(v)

396
1547

Question 19

19.

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

(i)

5
6
(ii)

2
3
(iii)

1
2
(iv)

3
4
(v)

4
5

Question 20

20.

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)

3
4
(ii)

0
(iii)

1
2
(iv)

2
5
(v)

1
4

Question 21

21.

A die is thrown twice. What is the probability that 1 will not come up either time?

(i)

25
36
(ii)

2
3
(iii)

13
18
(iv)

11
36
(v)

26
37

Question 22

22.

A lot of 23 bulbs contain 13 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)

10
23
(ii)

5
11
(iii)

13
22
(iv)

4
11
(v)

9
22

Question 23

23.

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

(i)

1
4
(ii)

1
8
(iii)

7
8
(iv)

0
(v)

2
9

Question 24

24.

Two coins are tossed simultaneously 150 times and it was observed that both heads appeared 25 times. If two coins are tossed simultaneously at random, what is the probability of getting both heads?

(i)

5
6
(ii)

1
3
(iii)

0
(iv)

1
6
(v)

2
7

Question 25

25.

What is the probability of an impossible event?

(i)

3
4
(ii)

0
(iii)

1
2
(iv)

1
(v)

1
4

Assignment Key