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1989 AIME Question 5

AIME · 1989 AIME

Question 5

When a certain biased coin is flipped five times, the probability of getting heads exactly once is not equal to $0$ and is the same as that of getting heads exactly twice. Let $\frac{i}{j},$ in lowest terms, be the probability that the coin comes up heads in exactly $3$ out of $5$ flips. Find $i+j.$