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In a meeting, 70% of the members favour ...

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).

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The correct Answer is:
E(X)=0.7 and Var(X)=0.21
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