The Pew Internet & American Life Project compiles data on smartphone ownership and publishes the results in the document Smartphone Ownership. The first two columns of the following table provide a percentage distribution for age of U.S. adults. The third column of the table shows the percentage of people in each age group who own a smartphone.

Age group Percentage Percentage who

(years) of adults own a smartphone 18–24 12.5 79 25–34 18.0 81 35–44 16.7 69 45–54 17.5 55 55–64 16.4 39 65+ 18.9 18 Suppose that a U.S. adult is selected at random. Determine the probability that the person selected

a. owns a smartphone, given that he or she is between 18 and 24 years old.

b. owns a smartphone

c. is between 18 and 24 years old, given that he or she owns a smartphone.

d. Interpret your answers in parts (a)–

(c) in terms of percentages.

* Quinella and Trifecta Wagering.