# NCERT Class 12-Mathematics: Chapter –13 Probability Part 5

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Question 14:

Let A and B be two events such that , and .

Then equals

(A)

(B)

(C)

(D)

Question 15:

If A and B are independent events such that and , then which of the following is not correct?

(A) and are mutually exclusive

(B) and are independent

(C) and are independent

(D) and are independent

Question 16:

Let be a discrete random variable. The probability distribution of is given below:

Then E (X) is equal to

(A)

(B)

(C)

(D)

Question 17:

Let be a discrete random variable assuming values with probabilities , respectively. Then variance of is given by

(A)

(B)

(C)

(D)

## Fill in the Blanks in Examples 18 and 19

Question 18:

If A and B are independent events such that and ___________

Question 19:

If and are independent events then ________

.

### State Whether Each of the Statement in Examples 20 to 22 is True or False

Question 20:

Let A and B be two independent events. Then

Because when events A and B are independent.

Question 21:

Three events A, B and C are said to be independent if .