Subject: Expected Value

Hi! I was wandering if you can hlep explain the expected value to this problem. I am aware how to do expected value but i come to blank with this problem.
Thanks! Cindy

A game consists of rolling a single fair die. If a number great than 4 is rolled you win the number of dollars showing on the die. If any other number is rolled, you receive $1.00. What is the expected value of this game?

THANKS

Hi Cindy, In this case we have the following probability distribution of our profit: 

Number rolled  1   2   3   4   5   6
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Profit         1   1   1   1   5   6
_____________________________________
Probability   1/6 1/6 1/6 1/6 1/6 1/6

By the definition of expected value

Expected Value(Profit)
= $1*(1/6) + $1*(1/6) + $1*(1/6) + $1*(1/6) + $5*(1/6) + $6*(1/6)
= $15/6 = $2.5

Andrei
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