Assume we have the following PDF for the random variable X x 0 1 2 3...

Question

Question

Assume we have the following PDF for the random variable X

x	0	1	2	3	4
f ( x )	.2	.1	.15	.3	.25

If Var ( X ) = 2.11, what is Var(3-2X)

math Statistics-And-Probability

Answer 1

Answer #1

Var(3-2X) = Var(3) + Var(2X)

= 0 + 2²*Var(x)------------------------(Var(const) = 0 and Var(ax) = a²Var(X))

=4*2.11

= 8.44

Answer 2

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