SOLUTION: Probability If you toss seven fair coins, in how many ways can you obtain each result? at least 2 heads ("At least two" is the complement "of zero or one")

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Question 843622: Probability
If you toss seven fair coins, in how many ways can you obtain each result?
at least 2 heads ("At least two" is the complement "of zero or one")

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
There are 2%5E7 or 128 possible outcomes.
One of them has zero heads.
TTTTTTT
Seven of them have one head.
TTTTTTH
TTTTTHT
TTTTHTT
TTTHTTT
TTHTTTT
THTTTTT
HTTTTTT
So then the probability of "at least 2 heads" is,
P=1-%281%2B7%29%2F128=1-8%2F128=1-1%2F16=15%2F16