Probability: CBSE Class 10 Previous Year Questions

Assertion (A): The probability of getting number 8 on rolling a die is zero (0).
Reason (R): The probability of an impossible event is zero (0).

1. (A)Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
2. (B)Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
3. (C)Assertion (A) is true, but Reason (R) is false.
4. (D)Assertion (A) is false, but Reason (R) is true.

Probability of getting an irrational number at random from the numbers $\sqrt{3},\sqrt{4},3\sqrt{9},3\sqrt{8},\sqrt{5},0,4^{\frac{3}{2}}$ is :

1. (A)0
2. (B)$\frac{4}{7}$
3. (C)$\frac{3}{7}$
4. (D)1

Assertion (A) : The probability of an event can not be $\frac{1}{0.9}$.
Reason (R) : $0\le P(E)\le 1$ for an event E.

1. (A)Both, Assertion (A) and Reason (R) are true and Reason (R) is correct explanation of Assertion (A).
2. (B)Both, Assertion (A) and Reason (R) are true, but Reason (R) is not correct explanation for Assertion (A).
3. (C)Assertion (A) is true, but Reason (R) is false.
4. (D)Assertion (A) is false, but Reason (R) is true.

A bag contains some red and some white balls. A ball is drawn at random from the bag. If the probability of getting a red ball is $\frac{2}{7}$, then the probability of getting a white ball is

1. (A)$\frac{1}{14}$
2. (B)$\frac{5}{7}$
3. (C)$\frac{1}{7}$
4. (D)$\frac{2}{7}$

A card is drawn from a well-shuffled deck of 52 playing cards. The probability of getting a queen of spade is

1. (A)$\frac{1}{26}$
2. (B)$\frac{1}{52}$
3. (C)0
4. (D)$\frac{1}{4}$

Assertion (A) : The probability that a leap year has 53 Mondays is $\frac{2}{7}$.
Reason (R) : The probability that a non-leap year has 53 Mondays is $\frac{5}{7}$.

1. (A)Both, Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
2. (B)Both, Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
3. (C)Assertion (A) is true, but Reason (R) is false.
4. (D)Assertion (A) is false, but Reason (R) is true.

The probability for a randomly selected number out of 1, 2, 3, 4, ..., 25 to be a composite number is :

1. (A)$\frac{15}{25}$
2. (B)$\frac{10}{25}$
3. (C)$\frac{11}{25}$
4. (D)$\frac{9}{25}$

Assertion (A) : If probability of happening of an event is 0.2p, $p>0$, then p can't be more than 5.
Reason (R) : $P(\overline{E})=1-P(E)$ for an event E.

1. (A)Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
2. (B)Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
3. (C)Assertion (A) is true, but Reason (R) is false.
4. (D)Assertion (A) is false, but Reason (R) is true.

Which of the following can not be the probability of an event ?

1. (A)$\frac{39}{100}$
2. (B)$\frac{0.001}{20}$
3. (C)$\frac{10}{0.2}$
4. (D)10%

Meena calculates that the probability of her winning the first prize in a lottery is 0.08. If total 800 tickets were sold, the number of tickets bought by her, is

1. (A)64
2. (B)640
3. (C)100
4. (D)10