An allergy drug is tested by giving 120 people the drug and 100 people a placebo. A control group consists of 80 people who were given no treatment. The number of people in each group who showed improvement appears in the table below.

Allergy drug Placebo Control Total

Improvement 65 42 31 138

No improvement 55 58 49 162

Total 120 100 80 300

16. What is the probability that a randomly selected person in the study was given either the drug or the placebo?

17. What is the probability that a randomly selected person either improved or did not improve?

18. What is the probability that a randomly selected person either was given the drug or improved?

19. What is the probability that a randomly selected person was given the drug and improved?

20. Assume that body temperatures of healthy adults are normally distributed with a mean of 98.20°F and a standard deviation of 0.62°F (based on data from University of Maryland researchers). If you have a body temperature of 99.00°F, what is your percentile score?