Anew medicine was given to a sample of 100 hospital patients. of the total, 65 patients reacted favorably, 9 reacted unfavorably, and 26 were unaffected by the drug. assume that this sample is representative of the entire population. if this medicine is given to mr. and mrs. rivera and their son carlos, what is the probability mrs. rivera reacts favorably? (assume independence.)

Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?

Precalculus question, image attached.