SOLUTION: A bag contains 1 gold marbles, 8 silver marbles, and 25 black marbles. Someone offers to play this game: You randomly select one marble from the bag. If it is gold, you win $4. If

Algebra ->  Probability-and-statistics -> SOLUTION: A bag contains 1 gold marbles, 8 silver marbles, and 25 black marbles. Someone offers to play this game: You randomly select one marble from the bag. If it is gold, you win $4. If       Log On


   



Question 1183051: A bag contains 1 gold marbles, 8 silver marbles, and 25 black marbles. Someone offers to play this game: You randomly select one marble from the bag. If it is gold, you win $4. 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 by ikleyn(52814) About Me  (Show Source):
You can put this solution on YOUR website!
.
A bag contains 1 gold marbles, 8 silver marbles, and 25 black marbles.
Someone offers to play this game:
You randomly select one marble from the bag.
If it is gold, you win $4. If it is silver, you win $2. If it is black, you lose $1.
What is your expected value if you play this game?
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In all, there are  1 + 8 + 25 = 34  marbles in the bag.


The expected value of the game is


    E = 4%2A%281%2F34%29+%2B+2%2A%288%2F34%29+-+1%2A%2825%2F34%29 = %284+%2B+16+-+25%29%2F34 = -5%2F34  of a dollar.


In other words, playing many times, you statistically lose 5%2F34 = 0.147 dollars per game, in average.

Solved, answered and explained.