Exemple 25:

In a survey of a group of men, the heights in the 20-29 age group were normally distributed, with a mean of 67.2 inches and a standard deviation of 3.0 inches. (d) below. (a) Find the probability that a study participant has a height that is less than 68 inches. The probability that the study participant selected at random is less than 68 inches tall is (Round to four decimal places as needed.) (b) Find the probability that a study participant has a height that is between 68 and 71 inches. The probability that the study participant selected at random is between 68 and 71 inches tall is (Round to four decimal places as needed.) (c) Find the probability that a study participant has a height that is more than 71 inches. The probability that the study participant selected at random is more than 71 inches tall is .(Round to four decimal places as needed.) (d) Identify any unusual events. Explain your reasoning. Choose the correct answer below. O A. There are no unusual events because all the probabilities are greater than 0.05. O B. The events in parts (a) and (c) are unusual because its probabilities are less than 0.05. O C. The event in part (a) is unusual because its probability is less than 0.05. O D. The events in parts (a), (b), and (c) are unusual because all of their probabilities are less than 0.05