SOLUTION: Seven coins are tossed. What is the probability of getting at least five tails?

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Question 1064120: Seven coins are tossed. What is the probability of getting at least five tails?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
P%28X%29=C%287%2CX%29%280.5%29%5EX%2A%280.5%29%5E%287-X%29=C%287%2CX%29%2A%280.5%29%5E7
At least 5 means X=5,6, and 7.
P=P%285%29%2BP%286%29%2BP%287%29
P=%281%2F128%29%2821%2B7%2B1%29
P=%281%2F128%29%2829%29
P=29%2F128