# Question: Let X1 and X2 be independent chi square random variables with

Let X1 and X2 be independent chi-square random variables with r1 and r2 degrees of freedom, respectively. Let Y1 = (X1/r1)/(X2/r2) and Y2 = X2.

(a) Find the joint pdf of Y1 and Y2.

(b) Determine the marginal pdf of Y1 and show that Y1 has an F distribution.

(a) Find the joint pdf of Y1 and Y2.

(b) Determine the marginal pdf of Y1 and show that Y1 has an F distribution.

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