China Mathematical Competition

Question

Two persons roll two dice in turn. Whoever gets the sum number greater than 6 first will win the game. The probability for the person rolling first to win is ________.

Accepted Answer

The probability for rolling two dice to get the sum number greater than 6 is 2136 = 712. Therefore, the required probability is 712 + (512)^2 712 + (512)^4 712 + = 712 11 - 25144 = 1217.