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A coin is tossed 12 times. What is the probability of getting heads exactly 7 times?

User Azochz
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2 Answers

0 votes
17% chance I think.
User Neigaard
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4 votes

Answer:

Once the number of possible heads and tail in 12 tosses is
2^(12) =4096


(12!)/(\left(7!\right)\left(5!\right))\\\\(12\cdot \:11\cdot \:10\cdot \:9\cdot \:8)/(5!)\\\\(95040)/(120)\\\\792

So the probability of getting exactly 8 heads in 12 coin tosses is:
(792)/(4096)

User DrGabriel
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