According to the Centers for Disease Control and Prevention, the proportion of U.S. adults age 25 or older who smoke is .22. A researcher suspects that the rate is lower among U.S. adults 25 or older who have a bachelor's degree or higher education level. If the researcher took a sample of 100 US adults age 25 or older who have a bachelor's or higher and found that 15 of them smoked, which of the following would be the correct calculation for the test statistic?