1. The problem statement, all variables and given/known data You want to see if a coin is fair. You flip it 5 times and count the number of heads. If H is the number of heads obtained in five flips of the coin, what is the P-value of the test when H equals 4? 2. Relevant equations None 3. The attempt at a solution To solve this problem, I thought that it would be correct to use the binomial PDF, to answer the question "If the probability of getting heads is .5, then what are the chances of getting 4 heads in 5 flips?" This gives .15625, which is not the right P-value. The correct answer is 3/16, but how do I get this value? What probability distribution to I use to obtain this P-value?