Question

What is your expected value for a game where your probability of winning is 1/7 and your profit is four times your wager

Answer 1

-x(6/7) + 4x(1/7)

Explanation:

Since there was no net amount, I substituted it with x. Since there is a 1/7 chance of winning, it is being times with 4 times the wager (x). With there being a 1/7 chance of winning there is a 6/7 chance of losing. I put -x because that is the amount you would wager (spending money). If you do find a net amount be sure to substitute it for x.