Question 51
At a fair there is an appealing game: participation is free and a winner receives a prize. For each of the first four games the prize is one coin; for the fifth it is two coins. Nicola has probability $2/3$ of winning the prize in each game and decides to play 5 games. What is the probability that he wins at least 4 coins?
(A) $5(2/3)^5$; (B) $4(2/3)^5$; (C) $3(2/3)^5$; (D) $2(2/3)^5$; (E) $(2/3)^5$.
(A) $5(2/3)^5$; (B) $4(2/3)^5$; (C) $3(2/3)^5$; (D) $2(2/3)^5$; (E) $(2/3)^5$.