Question

Please Answer Fast.
Jack is playing a game of flipping a coin, He wins as soon as the coin lands on heads, and keeps flipping if the coin lands on tails. What is the minimum number of times Jack has to flip the coin to make sure that his chance of winning is more than 90%?

Answer 1

Answer:

Jack is playing a game of flipping a coin, He wins as soon as the coin lands on heads, and keeps flipping if the coin lands on tails. What is the minimum number of times Jack has to flip the coin to make sure that his chance of winning is more than 90%?

Answer 2

Answer:

So AA only flips on odd tosses. So the probability of winning would be

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Is that right? It seems that if AA only flips on odd tosses, this shouldn't matter. Either AA can win on his first toss, his second toss, ...., or his nthnth toss. So the third flip of the coin is actually AA's second toss. So shouldn't it be

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