Question 1087162: The probability of "heads" coming face-up on a single flip of a fair two-sided coin is 0.5.
You flip the coin a total of eight (8) times. What is the probability of getting exactly 6
"heads" in those 8 flips?
Answer by mathmate(429)   (Show Source):
You can put this solution on YOUR website! Question:
The probability of "heads" coming face-up on a single flip of a fair two-sided coin is 0.5.
You flip the coin a total of eight (8) times. What is the probability of getting exactly 6
"heads" in those 8 flips?
Solution:
There are different ways to solve this problem.
1. Since it is a fair coin, probability of going either way is 1/2.
We can make a tree diagram and get every branch with equal probabilities, and count those with exact 6 heads (there will be 2^8=256 entries)
2. Same as 1 above, but use a table instead (again with 256 outcomes)
3. easier way is to use the binomial distribution formula for x=6 out of n=8 with probability p=0.5.
P(6)=C(8,6)*p^(x)*(1-p)^(n-x)
=C(8,6)*(0.5)^6*(0.5)^2
=8*7/(1*2)/256
=7/32
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