EduSahara™ Worksheet

Question 1

1.

A survey of 150 men showed that only 130 of them know Telugu. Out of these men, if one is selected at random, what is the probability that the selected man knows Telugu?

(i)

2
15
(ii)

13
15
(iii)

14
15
(iv)

7
8
(v)

4
5

Question 2

2.

A coin is tossed 100 times and head appears 35 times. If the coin is tossed again, what is the probability of getting a tail?

(i)

7
20
(ii)

2
3
(iii)

3
5
(iv)

7
10
(v)

13
20

Question 3

3.

Which of the following are possible values of probability?

a)

-5.2

b)

0.5

c)

1

4

d)

5

e)

4

1

(i)

{e,a,b}
(ii)

{b,c}
(iii)

{d,c,b}
(iv)

{a,b}
(v)

{d,c}

Question 4

4.

There are 58 students in a class room of whom 28 are boys and 30 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a boy ?

(i)

14
29
(ii)

1
2
(iii)

15
29
(iv)

13
29

Question 5

5.

If P(E) =
0.5
, find P(
E
)

(i)

2.5
(ii)

7.5
(iii)

1.5
(iv)

0.5
(v)

8.5

Question 6

6.

Two coins are tossed simultaneously 130 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)

4
13
(ii)

5
13
(iii)

17
26
(iv)

9
26
(v)

10
27

Question 7

7.

A coin is tossed 70 times and tail appears 20 times. If the coin is tossed again, what is the probability of getting a head?

(i)

6
7
(ii)

5
7
(iii)

2
7
(iv)

4
7
(v)

3
4

Question 8

8.

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

28

10

19

23

25

13

5

4

26

19

What is the empirical probability that an engineer lives less than 25 km from her place of work?

(i)

8
11
(ii)

3
5
(iii)

3
10
(iv)

7
10
(v)

4
5

Question 9

9.

In a lottery, there are 16 prizes and 10 blanks. What is the probability of not getting a prize?

(i)

6
13
(ii)

5
13
(iii)

4
13
(iv)

3
7
(v)

8
13

Question 10

10.

A die is thrown 100 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)

3
10
(ii)

2
5
(iii)

7
10
(iv)

4
11
(v)

1
5

Question 11

11.

There are 62 students in a class room of whom 38 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)

13
32
(ii)

11
31
(iii)

19
31
(iv)

12
31
(v)

13
31

Question 12

12.

A die is thrown 380 times. The number 1 appears on the upper face 74 times. Now the die is thrown at random. What is the probability of getting a 1 ?

(i)

1
5
(ii)

38
191
(iii)

153
190
(iv)

37
190
(v)

18
95

Question 13

13.

Two players Spoorthi and Jasmine play a tennis match. It is known that the probability of Spoorthi winning the match is 0.33. What is the probability of Jasmine winning the match?

(i)

67
100
(ii)

33
50
(iii)

68
101
(iv)

17
25
(v)

33
100

Question 14

14.

In a lottery, there are 25 prizes and 14 blanks. What is the probability of getting a prize?

(i)

25
39
(ii)

8
13
(iii)

13
20
(iv)

2
3
(v)

14
39

Question 15

15.

Three coins are tossed simultaneously 255 times with the following frequencies of different outcomes :

Outcome

3 heads

2 heads

1 heads

No heads

Frequency

40

60

70

85

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

(i)

3
17
(ii)

5
17
(iii)

5
18
(iv)

4
17
(v)

13
17

Question 16

16.

The following table shows the blood-groups of 396 students of a class.

Blood group

AB

B

A

O

Number of students

63

90

117

126

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

(i)

4
11
(ii)

3
11
(iii)

8
23
(iv)

15
22
(v)

7
22

Question 17

17.

234 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

81

90

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

(i)

5
13
(ii)

6
13
(iii)

8
13
(iv)

3
7
(v)

4
13

Question 18

18.

Two coins are tossed simultaneously 130 times and it was observed that both tails appeared 120 times. If two coins are tossed simultaneously at random, what is the probability of getting both tails?

(i)

12
13
(ii)

1
(iii)

1
13
(iv)

13
14
(v)

11
13

Question 19

19.

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

(i)

2
3
(ii)

4
5
(iii)

5
6
(iv)

1
2
(v)

3
4

Question 20

20.

A die is thrown 370 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

40

60

75

80

85

If the die is thrown again randomly, find the probability of getting 3 as outcome.

(i)

6
37
(ii)

31
37
(iii)

7
37
(iv)

5
37
(v)

7
38

Question 21

21.

On a particular day, at a crossing in a city, the various types of 120 vehicles going past during a time-interval were observed as under:

Type of Vehicle

Four-wheeler

Three-wheeler

Two-wheeler

Frequency

25

40

55

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

(i)

1
3
(ii)

2
3
(iii)

1
2
(iv)

0

Question 22

22.

Which of the following are true?

a)

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

b)

P(E) - P(
E
) = 0

c)

P(E) + P(
E
) = 0

d)

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

e)

P(E) = 1 - P(
E
)

(i)

{d,e}
(ii)

{b,e,d}
(iii)

{c,a,d}
(iv)

{a,d}
(v)

{b,e}

Question 23

23.

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 unsure event is 0
d)	The probability of an imposible event can be > 1
e)	The probability of an impossible event is 1

(i)

{c,a}
(ii)

{d,b}
(iii)

{e,c,a}
(iv)

{d,b,a}
(v)

{a,b}

Question 24

24.

Which of the following experiments have equally likely outcomes?

a)	A man throws a die. The number on the top is either 3 or not 3
b)	A baby is born. It is a boy or girl
c)	A ball is hit. It reaches the boundary or not
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)

{e,a,b}
(ii)

{c,d,b}
(iii)

{b,d}
(iv)

{a,b}
(v)

{c,d}

Question 25

25.

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

18

23

21

14

1

10

9

11

9

15

2

25

14

6

3

What is the empirical probability that an engineer lives greater than 14 km from her place of work?

(i)

0
(ii)

1
2
(iii)

1
3
(iv)

2
3

Assignment Key