The Journal of Risk and Uncertainty (May 1992) published an article investigating the relationship of injury rate of drivers of all-terrain vehicles (ATVs) to a variety of factors. One of the more interesting factors studied, age of the driver, was found to have a strong relationship to injury rate. The article reports that prior to a safety-awareness program, 14% of the ATV drivers  were under age 12; another 13% were 12–15, and 48% were under age 25. Suppose an ATV driver is selected at random prior to the installation of the safety-awareness program.
a. Find the probability that the ATV driver is 15 years old or younger.
b. Find the probability that the ATV driver is 25 years old or older.
c. Given that the ATV driver is under age 25, what is the probability the driver is under age 12?
d. Are the events Under age 25 and Under age 12 mutually exclusive? Why or why not?
e. Are the events Under age 25 and Under age 12 independent? Why or why not?