d2touge wrote:
Kate and David each have $10. Together they flip a coin 5 times. Every time the coin lands on heads, Kate gives David $1. Every time the coin lands on tails, David gives Kate $1. After the coin is flipped 5 times, what is the probability that Kate has more than $10 but less than $15.
(A)\frac{5}{16}
(B)\frac{15}{32}
(C)\frac{1}{2}
(D)\frac{21}{32}
(E)\frac{11}{16}
[Reveal] Spoiler: OA
B
Source: GMAT Club Tests - hardest GMAT questions
So to answer this, we find the total combinations when you flip the coin
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