Round all answers to 2 decimals when appropriate

A certain tennis player makes a successful first serve 69% of the time. Assume that each serve is independent of the others. She averages 80 1st serves per match.

a) Out of 80 first serves, what is the probability that she makes 47 good 1st serves or fewer? (use binomcdf)

b) Find the mean and standard deviation for the number of good 1st serves out of 80 attempts.

Mean:      Standard Deviation:

c) Does the normal approximation apply? Explain.

 

d) Use the normal distribution to find the probability that she gets 47 good 1st serves or fewer out of 80 attempts.