EduSahara™ Worksheet

Question 1

1.

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

22

23

11

7

12

27

6

27

What is the empirical probability that an engineer lives less than 7 km from her place of work?

(i)

0
(ii)

1
8
(iii)

1
4
(iv)

7
8
(v)

2
9

Question 2

2.

A box contains 70 discs which are numbered from 1 to 70. If one disc is drawn at random from the box, find the probability that it bears a perfect square number.

(i)

3
35
(ii)

4
35
(iii)

1
7
(iv)

31
35
(v)

5
36

Question 3

3.

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

10

14

8

24

18

2

9

26

What is the empirical probability that an engineer lives greater than 24 km from her place of work?

(i)

0
(ii)

7
8
(iii)

2
9
(iv)

1
8
(v)

1
4

Question 4

4.

An unbiased die is thrown once. Find the probability of getting an even number?

(i)

3
4
(ii)

5
6
(iii)

1
2
(iv)

2
3
(v)

4
5

Question 5

5.

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
2
(ii)

2
5
(iii)

0
(iv)

1
4
(v)

3
4

Question 6

6.

52 cards are numbered 1,2,3,....52 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)

3
4
(ii)

5
6
(iii)

4
5
(iv)

2
3
(v)

1
2

Question 7

7.

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

(i)

1
4
(ii)

5
8
(iii)

1
2
(iv)

3
8
(v)

4
9

Question 8

8.

Which of the following are true?

a)	Probability of getting 101 marks out of 100 is 1.01
b)	If the probability is too less, it will become negative
c)	The probability of an event that is very likely to happen is 1
d)	If the probability of failing the exam is 0.8, the probability of passing the exam is 0.2
e)	The probability of an event that cannot happen is unknown

(i)

{b,d}
(ii)

{c,e,d}
(iii)

{d}
(iv)

{a,d}

Question 9

9.

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

(i)

0
(ii)

1
2
(iii)

2
5
(iv)

1
4
(v)

3
4

Question 10

10.

Which of the following are true?

a)

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

b)

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

c)

P(E) + P(
E
) = 0

d)

P(E) - P(
E
) = 0

e)

P(E) = 1 - P(
E
)

(i)

{d,b,a}
(ii)

{c,e,a}
(iii)

{c,e}
(iv)

{a,e}
(v)

{b,a}

Question 11

11.

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

(i)

35
(ii)

38
(iii)

36
(iv)

37
(v)

33

Question 12

12.

A die is thrown 50 times. Prime numbers appeared on the upper face 35 times. If a die is thrown at random, what is the probability of getting a prime number?

(i)

3
10
(ii)

4
5
(iii)

3
5
(iv)

7
10
(v)

8
11

Question 13

13.

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

(i)

1
2
(ii)

2
3
(iii)

5
6
(iv)

4
5
(v)

3
4

Question 14

14.

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

(i)

1
2
(ii)

3
4
(iii)

4
5
(iv)

5
6
(v)

2
3

Question 15

15.

A die is thrown twice. What is the probability that 2 will not come up either time?

(i)

26
37
(ii)

13
18
(iii)

25
36
(iv)

11
36
(v)

2
3

Question 16

16.

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

(i)

1
26
(ii)

1
52
(iii)

3
13
(iv)

1
13
(v)

1
4

Question 17

17.

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

(i)

49
(ii)

51
(iii)

52
(iv)

53
(v)

55

Question 18

18.

A box contains 15 white marbles, 33 red marbles, 27 orange marbles and 3 gray marbles. One marble is drawn at random from the box. Find the probability that the marble drawn is not white.

(i)

21
26
(ii)

10
13
(iii)

11
13
(iv)

22
27
(v)

5
26

Question 19

19.

A box contains 45 white marbles, 35 orange marbles, 15 gray marbles and 20 yellow marbles. One marble is drawn at random from the box. Find the probability that the marble drawn is gray.

(i)

1
6
(ii)

20
23
(iii)

3
23
(iv)

4
23
(v)

2
23

Question 20

20.

The following table shows the blood-groups of 324 students of a class.

Blood group

A

B

AB

O

Number of students

54

72

90

108

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

(i)

2
9
(ii)

1
3
(iii)

7
9
(iv)

1
9
(v)

3
10

Question 21

21.

A lot of 21 bulbs contain 11 defective ones. One bulb is drawn at random from the lot. What is the probability that this bulb is defective ?

(i)

11
21
(ii)

6
11
(iii)

10
21
(iv)

4
7

Question 22

22.

53 cards are numbered 1,2,3,....53 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 a prime number?

(i)

37
53
(ii)

17
54
(iii)

16
53
(iv)

15
53
(v)

17
53

Question 23

23.

An unbiased die is thrown once. Find the probability of getting a number between 1 and 6?

(i)

1
3
(ii)

2
3
(iii)

1
(iv)

3
4

Question 24

24.

A die is thrown 540 times. The number 2 appears on the upper face 74 times. Now the die is thrown at random. What is the probability of getting a 2 ?

(i)

2
15
(ii)

37
270
(iii)

38
271
(iv)

19
135
(v)

233
270

Question 25

25.

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

(i)

3
4
(ii)

2
5
(iii)

0
(iv)

1
2
(v)

1
4

Assignment Key