# Math Help - simple proof of expected value...

1. ## simple proof of expected value...

CV are random variables.
Whats a hint to show if C<=V, then E(C)<=E(V)?

if C<=V then
P(C=s)<=p(V=s) for all s
so summation of C*P(C=c) has to be smaller then summation of V*(V=v)
so then E(C)<=E(V)

thanks for helping

2. Originally Posted by Sneaky
CV are random variables.
Whats a hint to show if C<=V, then E(C)<=E(V)?

if C<=V then
P(C=s)<=p(V=s) for all s
so summation of C*P(C=c) has to be smaller then summation of V*(V=v)
so then E(C)<=E(V)

thanks for helping
Are they continuous rv's or discrete? (It looks from your working that you are assuming discrete?)