When flipping a fair coin three times in a row, what is the probability of getting at least one head? Express your answer as a simplified fraction.
7/8
There are 2³ = 8 total outcomes. The only outcome with no heads is getting three consecutive tails (TTT), which has a probability of 1/8. The probability of getting at least one head is 1 - 1/8 = 7/8.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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