Skip to content / Đến nội dung
ThichHocToan.com

2012 AMC 12A Question 11

AMC12 · 2012 AMC 12A

Question 11

Alex, Mel, and Chelsea play a game that has $6$ rounds. In each round there is a single winner, and the outcomes of the rounds are independent. For each round the probability that Alex wins is $\dfrac12,$ and Mel is twice as likely to win as Chelsea. What is the probability that Alex wins three rounds, Mel wins two rounds, and Chelsea wins one round?
  1. $\dfrac{5}{72}$
  2. $\dfrac{5}{36}$
  3. $\dfrac{1}{6}$
  4. $\dfrac{1}{3}$
  5. $1$