SOLUTION: Three fair coins are tossed. What is the probability that at least one is a head? (Enter the probability as a fraction.)

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Question 894926: Three fair coins are tossed. What is the probability that at least one is a head? (Enter the probability as a fraction.)
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Find the probability that there are no heads.
Then the sum of no heads and at least one head will sum to 1.
P%28NH%29=%281%2F2%29%281%2F2%29%281%2F2%29=1%2F8
So,
P%281H%29=1-1%2F8
P%281H%29=7%2F8