EduSahara™ Worksheet

Question 1

1.

A coin is tossed 60 times and tail appears 45 times. If the coin is tossed again, what is the probability of getting a head?

(i)

1
4
(ii)

2
5
(iii)

1
2
(iv)

3
4
(v)

0

Question 2

2.

A coin is tossed 90 times and head appears 60 times. If the coin is tossed again, what is the probability of getting a tail?

(i)

0
(ii)

1
2
(iii)

2
3
(iv)

1
3

Question 3

3.

Two coins are tossed simultaneously 110 times and it was observed that both heads appeared 40 times. If two coins are tossed simultaneously at random, what is the probability of getting both heads?

(i)

5
12
(ii)

5
11
(iii)

4
11
(iv)

7
11
(v)

3
11

Question 4

4.

Two coins are tossed simultaneously 120 times and it was observed that both tails appeared 70 times. If two coins are tossed simultaneously at random, what is the probability of getting both tails?

(i)

1
2
(ii)

5
12
(iii)

2
3
(iv)

7
12
(v)

8
13

Question 5

5.

A die is thrown 40 times. Prime numbers appeared on the upper face 30 times. If a die is thrown at random, what is the probability of getting a prime number?

(i)

1
(ii)

1
2
(iii)

3
4
(iv)

4
5
(v)

1
4

Question 6

6.

A survey of 90 men showed that only 55 of them know Urdu. Out of these men, if one is selected at random, what is the probability that the selected man knows Urdu?

(i)

11
18
(ii)

12
19
(iii)

7
18
(iv)

2
3
(v)

5
9

Question 7

7.

On a particular day, at a crossing in a city, the various types of 125 vehicles going past during a time-interval were observed as under:

Type of Vehicle

Two-wheeler

Four-wheeler

Three-wheeler

Frequency

35

40

50

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

(i)

2
5
(ii)

1
5
(iii)

3
5
(iv)

1
2

Question 8

8.

The following table shows the blood-groups of 315 students of a class.

Blood group

AB

B

O

A

Number of students

45

54

99

117

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

(i)

24
35
(ii)

11
35
(iii)

2
7
(iv)

12
35
(v)

1
3

Question 9

9.

There are 68 students in a class room of whom 32 are boys and 36 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a boy ?

(i)

8
17
(ii)

9
17
(iii)

7
17
(iv)

1
2

Question 10

10.

There are 50 students in a class room of whom 26 are boys and 24 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a girl ?

(i)

11
25
(ii)

12
25
(iii)

13
25
(iv)

1
2

Question 11

11.

In a lottery, there are 29 prizes and 20 blanks. What is the probability of getting a prize?

(i)

3
5
(ii)

20
49
(iii)

30
49
(iv)

29
49
(v)

4
7

Question 12

12.

In a lottery, there are 24 prizes and 13 blanks. What is the probability of not getting a prize?

(i)

13
37
(ii)

14
37
(iii)

12
37
(iv)

7
19
(v)

24
37

Question 13

13.

Which of the following experiments have equally likely outcomes?

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

(i)

{c,d,b}
(ii)

{e,a,b}
(iii)

{a,b}
(iv)

{b,d}
(v)

{c,d}

Question 14

14.

Which of the following are possible values of probability?

a)

3

8

b)

0.5

c)

5

d)

-4.5

e)

7

5

(i)

{a,b}
(ii)

{c,a}
(iii)

{d,b}
(iv)

{e,c,a}
(v)

{d,b,a}

Question 15

15.

If P(E) =
0.14
, find P(
E
)

(i)

1.86
(ii)

7.86
(iii)

0.86
(iv)

2.86
(v)

8.86

Question 16

16.

Which of the following are true?

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

(i)

{d,b}
(ii)

{c,a}
(iii)

{d,b,a}
(iv)

{a,b}
(v)

{e,c,a}

Question 17

17.

Which of the following are true?

a)

P(E) = 1 - P(
E
)

b)

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

c)

P(E) + P(
E
) = 0

d)

P(E) - P(
E
) = 0

e)

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

(i)

{c,e}
(ii)

{c,e,a}
(iii)

{a,e}
(iv)

{d,b,a}
(v)

{b,a}

Question 18

18.

Two players Ankitha and Reshma play a tennis match. It is known that the probability of Ankitha winning the match is 0.50. What is the probability of Reshma winning the match?

(i)

5
6
(ii)

1
2
(iii)

4
5
(iv)

3
4
(v)

2
3

Question 19

19.

A die is thrown 420 times. The number 3 appears on the upper face 66 times. Now the die is thrown at random. What is the probability of getting a 3 ?

(i)

12
71
(ii)

1
7
(iii)

11
70
(iv)

6
35
(v)

59
70

Question 20

20.

207 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

54

72

81

Compute the probability of the family, chosen at random, having 2 girls.

(i)

9
23
(ii)

8
23
(iii)

10
23
(iv)

14
23
(v)

5
12

Question 21

21.

Three coins are tossed simultaneously 195 times with the following frequencies of different outcomes :

Outcome

3 heads

2 heads

1 heads

No heads

Frequency

40

45

50

60

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

(i)

4
13
(ii)

9
13
(iii)

5
13
(iv)

5
14
(v)

3
13

Question 22

22.

A die is thrown 395 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

30

35

45

80

90

115

If the die is thrown again randomly, find the probability of getting 5 as outcome.

(i)

19
79
(ii)

61
79
(iii)

18
79
(iv)

19
80
(v)

17
79

Question 23

23.

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

2

16

29

27

27

11

22

23

25

5

20

10

15

21

21

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

(i)

1
5
(ii)

1
(iii)

3
5
(iv)

4
5
(v)

5
6

Question 24

24.

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

14

20

8

11

13

21

24

29

13

22

10

4

17

2

What is the empirical probability that an engineer lives greater than 29 km from her place of work?

(i)

1
2
(ii)

1
(iii)

3
4
(iv)

1
4
(v)

0

Assignment Key