SOLUTION: A coin is flipped eleven times in succession. In how many ways can at least nine heads occur?

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Question 1125007: A coin is flipped eleven times in succession. In how many ways can at least nine heads occur?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
at least 9 heads means 9, 10, or 11 heads
for 11, it is (1/2)^11 or 0.0005
for 10 it is 10*(1/2)^10*(1/2)=0.0049
For 9 it is 55*.5^11 or 0.0269
That sum is the answer or 0.0323