4b Intro to Credibility Theory question 2.11

Sheri De La Boursodiere ( (no email) )
Thu, 4 Mar 1999 11:43:16 -0800

Given f(y)= 0 y<0
.25 y=0
.75e^-y y>0

The solution in the book is E[Y^3|y>0]=Integral from o to infinity of
(y^3)(e^-y)dy = 6

Why isn't the solution E[Y^3|y>0]=Integral from o to infinity of
(y^3)(.75e^-y)dy = .75 x 6 = 4.5 ?

Sheri.
Can someone help me figure out why I am .75 off on this solution?