Unused paid vacation time. According to a 2019 Bankrate survey, most Americans do not use all of their paid vacation days. The most likely reason cited was that vacations are too expensive. Consider the survey question: “How many of your paid vacation days do you plan to use (this year)?” The results are summarized in the accompanying table. Response Percentage All 38 Almost all 21 About half 17 About a quarter 7 Less than a quarter 5 None 6 Unsure (because I have unlimited days) 6 Source: “Survey: High costs are keeping many Americans from summer vacation”, www.bankrate.com, April 25, 2019.

a. What is the probability that a randomly selected American with paid vacation time will use all of their paid vacation days this year?

b. What is the probability that a randomly selected American with paid vacation time will use at least half of their paid vacation days this year?