A smoking cessation program advertises that 60% of all participants in its program quit smoking for at

Question:

A smoking cessation program advertises that 60% of all participants in its program quit smoking for at least 6 months. Suppose Consumer Checkup surveyed 400 "graduates" of the program and found that 220 had not smoked for 6 months following the end of the program. What is the probability that this can happen if the advertising claim is true?