Math
posted by B.B. on .
On a TV game show, the contestant is asked to select a door and then is rewarded with the prize behind the door selected. If the doors can be selected with equal probability, what is the expected value of the selection if the three doors have behind them a $40,000 foreign car, a $3 silly straw, and a $50 mathematics textbook?
Answer: 1/3 but I don't think that this correct.
Could someone please help me with this problem?
Thanks.

OF course it is not correct. Expected Value is in dollars.
EV=1/3(40,000) + 1/3 (3) + 1/3 (50)
http://en.wikipedia.org/wiki/Expected_value 
So then, my answer should be this:
13,333.33333+1+16.66666667= 13,351 is this correct?
Thanks. 
"Expected Value is in dollars."
Do not forget your units. 13,351 is the correct value, but your answer should be $13,351.00 
Thanks.