If a person rolls doubles when tossing two dice, the roller profits $100. If the game is fair, how much should the person pay to play the game?
A)$20
B)$100
C)$99
D)$97

Question

Quizplus · Accepted Answer

The probability of rolling doubles with two dice is 1/6, since there are 6 possible doubles (1-1, 2-2, 3-3, 4-4, 5-5, 6-6) out of 36 possible outcomes (6 sides on the first die times 6 sides on the second die). For the game to be fair, the expected value of playing should be zero. If the profit for rolling doubles is $100, then the cost of playing should be the profit times the probability of winning: $100 * (1/6) = $16.67. However, since none of the options exactly match this calculation, the closest option, $20, is considered correct.

If a Person Rolls Doubles When Tossing Two Dice, the Roller