EduSahara™ Worksheet

Question 1

1.

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

13

15

7

19

27

23

8

30

16

What is the empirical probability that an engineer lives less than 15 km from her place of work?

(i)

1
2
(ii)

2
3
(iii)

0
(iv)

1
3

Question 2

2.

Two coins are tossed simultaneously 60 times and it was observed that both heads appeared 30 times. If two coins are tossed simultaneously at random, what is the probability of getting both heads?

(i)

4
5
(ii)

5
6
(iii)

2
3
(iv)

3
4
(v)

1
2

Question 3

3.

What is the probability of an impossible event?

(i)

1
(ii)

0
(iii)

3
4
(iv)

1
2
(v)

1
4

Question 4

4.

66 cards are numbered 1,2,3,....66 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 16?

(i)

8
33
(ii)

25
33
(iii)

26
33
(iv)

13
17
(v)

8
11

Question 5

5.

A lot of 24 bulbs contain 7 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)

16
23
(ii)

17
24
(iii)

17
23
(iv)

15
23
(v)

7
23

Question 6

6.

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

(i)

3
4
(ii)

1
2
(iii)

4
5
(iv)

2
3
(v)

5
6

Question 7

7.

A bag contains 8 black balls, 12 orange balls, 48 blue balls and 16 pink balls. One ball is drawn at random from the bag. Find the probability that the ball drawn is blue or black.

(i)

2
3
(ii)

1
(iii)

1
3
(iv)

3
4

Question 8

8.

If P(E) =
0.4
, find P(
E
)

(i)

7.6
(ii)

8.6
(iii)

2.6
(iv)

0.6
(v)

1.6

Question 9

9.

A die is thrown 80 times. Prime numbers appeared on the upper face 50 times. If a die is thrown at random, what is the probability of getting a prime number?

(i)

5
8
(ii)

1
2
(iii)

2
3
(iv)

3
4
(v)

3
8

Question 10

10.

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

(i)

25
36
(ii)

11
36
(iii)

13
18
(iv)

26
37
(v)

2
3

Question 11

11.

A bag contains 36 orange balls, 12 red balls, 36 yellow balls and 8 pink balls. One ball is drawn at random from the bag. Find the probability that the ball drawn is neither yellow nor red.

(i)

11
23
(ii)

1
2
(iii)

12
23
(iv)

10
23

Question 12

12.

On a particular day, at a crossing in a city, the various types of 165 vehicles going past during a time-interval were observed as under:

Type of Vehicle

Two-wheeler

Four-wheeler

Three-wheeler

Frequency

30

65

70

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

(i)

2
11
(ii)

1
11
(iii)

9
11
(iv)

1
4
(v)

3
11

Question 13

13.

In a lottery, there are 19 prizes and 11 blanks. What is the probability of getting a prize?

(i)

3
5
(ii)

11
30
(iii)

20
31
(iv)

19
30
(v)

2
3

Question 14

14.

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 number divisible by 5.

(i)

4
5
(ii)

1
3
(iii)

0
(iv)

1
5
(v)

2
5

Question 15

15.

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

(i)

1
(ii)

3
4
(iii)

1
2
(iv)

4
5
(v)

1
4

Question 16

16.

Which of the following are true?

a)

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

b)

P(E) + P(
E
) = 0

c)

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

d)

P(E) - P(
E
) = 0

e)

P(E) = 1 - P(
E
)

(i)

{a,c}
(ii)

{b,e,c}
(iii)

{d,a,c}
(iv)

{c,e}
(v)

{b,e}

Question 17

17.

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)

1
4
(ii)

1
2
(iii)

2
5
(iv)

0
(v)

3
4

Question 18

18.

Three coins are tossed simultaneously 220 times with the following frequencies of different outcomes :

Outcome

3 heads

2 heads

1 heads

No heads

Frequency

45

50

60

65

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

(i)

4
11
(ii)

2
11
(iii)

1
3
(iv)

3
11
(v)

8
11

Question 19

19.

An unbiased die is thrown once. Find the probability of getting a 1?

(i)

0
(ii)

1
3
(iii)

5
6
(iv)

2
7
(v)

1
6

Question 20

20.

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

(i)

1
4
(ii)

1
26
(iii)

3
13
(iv)

1
13
(v)

1
52

Question 21

21.

There are 54 students in a class room of whom 20 are boys and 34 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a girl ?

(i)

17
27
(ii)

2
3
(iii)

10
27
(iv)

16
27
(v)

9
14

Question 22

22.

324 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

63

117

144

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

(i)

2
9
(ii)

8
37
(iii)

7
36
(iv)

1
6
(v)

29
36

Question 23

23.

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

(i)

3
4
(ii)

1
2
(iii)

0
(iv)

1
4
(v)

2
5

Question 24

24.

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

(i)

5
6
(ii)

4
5
(iii)

3
4
(iv)

1
2
(v)

2
3

Question 25

25.

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)

0
(ii)

1
2
(iii)

3
4
(iv)

1
4
(v)

2
5

Assignment Key