The present worth of an investment project is described by the following equation:

PW = 20X + 8XY

where X and Y are statistically independent discrete random variables with the following PDFs:

Case 1

PDF of X

Value Probability

$33 0.6

$45 0.5

PDF of Y

Value Probability

$49 0.4

$72 0.6

Case 2

PDF of X

Value Probability

$21 0.6

$82 0.4

PDF Y

Value Probability

$32 04

$72 0.6