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Given Kudos: 6
A coin is tossed five times. What is the probability that th
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04 Oct 2022, 06:37
Umm... hi everyone, please don't calculate here. Remember, that's what the writer of the test wants you to do, but it's unnecessary.
The GRE is testing you on what's known as Gambler's Fallacy, or in simpler terms, the past does not predict the future. No matter what happened during the previous flips, it won't affect the fourth flip taken in isolation.
Go back to the wording of the question: it's specifically only discussing the fourth flip.
Any given flip taken alone will have a probability of 1/2, therefore the fourth flip has a probability of 1/2.
(Just like the first, second, third, and fifth would if isolated.)
Answer C.