Question

A bag contains 1 gold marbles, 7 silver marbles, and 25 black marbles. Someone offers to play this game: You randomlyselect one marble from the bag. If it is gold, you win $3. If it is silver, you win $2. If it is black, you lose $1.What is your expected value if you play this game?

Answer 1

Okay, here we have this:

Considering the provided information, we are going to calculate the expected value for the game, so we obtain the following:

We will substitute in the following formula:

Expected Value=(Black Gain)*Black Chance (Gold Gain)*Gold Chance+(Silver Gain)*Silver Chance

Expected Value=(-1)*(25/33)+(3)*(1/33)+(2)*(7/33)

Expected Value≈-0.24

Finally we obtain that the expected value is approximately $-0.24.