﻿ Two dice are thrown simultaneously. If X denotes the number of sixes, find the expectation of X. : Kaysons Education

# Two Dice Are Thrown Simultaneously. If X Denotes The Number Of Sixes, Find The Expectation Of X.

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## Question

### Solution

Correct option is

Clearly, X can take values 0, 1 and 2.

We have

P(X = 0) = Probability of not getting six on any dice =

P(X = 1) = Probability of getting one six =

P(X = 2) = Probability of getting two sixes =

Thus, the probability distribution of X is given by

Computation of mean variance

 xi pi = P(X = xi) pi xi 0 25/36 0 0 1 10/36 10/36 10/36 2 1/36 2/36 4/36

We have

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