11. Silvia and Luigi challenge each other by rolling a die multiple times. Each time an even number comes up, Silvia scores a point; when an odd number comes up, Luigi scores a point. The game is won by the first to score 5 points. After 5 rolls, Silvia is leading 4 to 1. What is the probability that Silvia will win the game?
(A) $4 / 5$
(B) $5 / 6$
(C) $7 / 8$
(D) $3 / 4$
(E) $15 / 16$
(11) The correct answer is $(E)$.

Luigi wins the game only if he scores a point with all four consecutive throws. Since the throws are independent events, his probability of winning is $(1 / 2)^{4}=1 / 16$ and the probability that Silvia wins is therefore $15 / 16$.

Problem proposed by Carmelo Di Stefano.