Let X be a random variable such that P(X = 1) = 0.4 and P(X =...

Let X be a random variable such that P(X = 1) = 0.4 and P(X = 0) = 0.6. Compute Var(X).

Expert Solution

x p xp x²p

1 0.4 0.4 0.4

0 0.6 0 0

---------------------------------------------------------------------------------------------

Total 0.4 0.4

So,

E(X) = 0.4

Var(X) = E(X²) - (E(X))²

= 0.4 - 0.4² = 0.24

So,

Answer is:

0.24

milcah answered 4 months ago

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