A hypothetical population consists of eight individuals ages 13, 15, 17, 21, 22, 23, 26, and 30 years. (Enter your answers to three decimal places.)
(a) What is the probability that a person in this population is a teenager?
(b) What is the probability of selecting a participant who is at least 20 years old?
(c) What is the probability of selecting a participant older than 30?