# Exam P Practice Problem 17 – Finding Variance of a Sum

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Problem 17A
Suppose that $X$ and $Y$ are random losses jointly distributed according to the density function $f(x,y)=2x$ where $0 and $0. Find the variance of the sum of the two losses.

Problem 17B
Suppose that $X$ and $Y$ are random losses jointly distributed according to the density function $f(x,y)=0.05 \ e^{-0.5 \ x}$ where $0 and $0. Find the variance of the sum of the two losses.

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