Question

You flip a coin three times. what is the probability of getting heads on only one of your flips?

Answer 1

There are 8 possible outcomes. So the quickest way to calculate it is using the binomial distribution.

P(X=k)= nCk pk(1-p)(n-k)
nCk denotes combination and is calculated as n!/[(n-k)!k!]
for a coin both p and (1-p) =.5

for part a we have n=3 and k=1
{3!/(2! 1!)} (.5)1(.5)2
this simplifies to 3(.5)3 or 3/8 and that is the answer.

Answer 2

I guess this is wrong answer