Exercise 5: Mogul Magazine has recently completed an analysis of its customer base. It has determined that 75% of the issues sold each month are subscriptions and the other 25% are sold at newsstands. It has also determined that the ages of its subscribers are normally distributed with a mean of 44.5 and a standard deviation 7.42 years, whereas the ages of its newsstand customers are normally distributed with of 36.1 and a standard deviation of 8.20 years.
1) Mogul would like to make the following statement to its advertisers: "80% of our subscribers are between the age of ...... and ....... Your job is to fill in the blanks choosing a range that is symmetric around the means. (In other words, the mean age of subscribers should be the midpoint of the range.)
2) What proportion of Mogul's newsstand customers have ages in the range you gave in 1)?
