In a meeting, 70% of the members favour and 30% oppose a certain proposal. A member is selected at random and we take X = 0 if he opposed, and X = 1 if he is in favour. Find E(X) and Var (X).

Answer

N/a

Explanation

Given, `P(X=0)=30%=30/100=3/10`
`P(X=1)=70%=70/100=7/10`
Therefore, the probability distribution is:

`:.` Mean of `X=E(X)=sumXP(X)`
`=0xx3/10+1xx7/10=7/10`
Variance of `X=sumX^(2)P(X)-("mean")^(2)`
`=0^(2)xx3/10+1^(2)xx7/10-(7/10)^(2)`
`=7/10-49/100=21/100`