EduSahara™ Worksheet

Question 1

1.

What is the probability of a sure event?

(i)

1
4
(ii)

1
2
(iii)

3
4
(iv)

1
(v)

0

Question 2

2.

What is the probability of an impossible event?

(i)

3
4
(ii)

1
2
(iii)

1
4
(iv)

0
(v)

1

Question 3

3.

There are 68 students in a class room of whom 30 are boys and 38 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a boy ?

(i)

15
34
(ii)

7
17
(iii)

8
17
(iv)

16
35
(v)

19
34

Question 4

4.

There are 50 students in a class room of whom 20 are boys and 30 are girls. From these students, one is choosen at random. What is the probability that the choosen student is a girl ?

(i)

2
3
(ii)

3
5
(iii)

4
5
(iv)

2
5

Question 5

5.

In a lottery, there are 10 prizes and 19 blanks. What is the probability of getting a prize?

(i)

19
29
(ii)

9
29
(iii)

10
29
(iv)

11
29
(v)

11
30

Question 6

6.

In a lottery, there are 27 prizes and 17 blanks. What is the probability of not getting a prize?

(i)

27
44
(ii)

17
44
(iii)

4
11
(iv)

9
22
(v)

2
5

Question 7

7.

Which of the following are true?

a)	Probability of getting 110 marks out of 100 is 1.1
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 0.67, the probability of passing the exam is 0.33
e)	The probability of an event that cannot happen is unknown

(i)

{d}
(ii)

{a,d}
(iii)

{b,d}
(iv)

{c,e,d}

Question 8

8.

Which of the following experiments have equally likely outcomes?

a)	A man throws a die. The number on the top is either 5 or not 5
b)	A ball is hit. It reaches the boundary or not
c)	A baby is born. It is a boy or girl
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,c}
(ii)

{a,c}
(iii)

{b,d,c}
(iv)

{c,d}
(v)

{b,d}

Question 9

9.

Which of the following are possible values of probability?

a)

0.4

b)

-5.2

c)

2

6

d)

4

e)

8

3

(i)

{a,c}
(ii)

{d,c,a}
(iii)

{b,a}
(iv)

{e,b,a}
(v)

{d,c}

Question 10

10.

If P(E) =
0.11
, find P(
E
)

(i)

2.89
(ii)

1.89
(iii)

8.89
(iv)

0.89
(v)

7.89

Question 11

11.

Which of the following are true?

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

(i)

{b,e,d}
(ii)

{d,e}
(iii)

{b,e}
(iv)

{c,a,d}
(v)

{a,d}

Question 12

12.

Which of the following are true?

a)

P(E) - P(
E
) = 0

b)

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

c)

P(E) + P(
E
) = 0

d)

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

e)

P(E) = 1 - P(
E
)

(i)

{d,a,b}
(ii)

{c,e}
(iii)

{c,e,b}
(iv)

{a,b}
(v)

{b,e}

Question 13

13.

Two players Roja and Trisha play a tennis match. It is known that the probability of Roja winning the match is 0.29. What is the probability of Trisha winning the match?

(i)

18
25
(ii)

7
10
(iii)

72
101
(iv)

71
100
(v)

29
100

Question 14

14.

Sarojini and Saraswathi are friends. What is the probability that both will have different birthdays? (ignoring a leap year).

(i)

364
365
(ii)

363
365
(iii)

1
(iv)

365
366
(v)

1
365

Question 15

15.

Rita and Pooja are friends. What is the probability that both will have same birthdays? (ignoring a leap year).

(i)

364
365
(ii)

2
365
(iii)

0
(iv)

1
183
(v)

1
365

Question 16

16.

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)

3
4
(v)

1
4

Question 17

17.

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 18.00 cm?

(i)

613
910
(ii)

148
455
(iii)

298
911
(iv)

297
910
(v)

149
455

Question 18

18.

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)

1
16
(ii)

0
(iii)

2
17
(iv)

15
16
(v)

1
8

Assignment Key