posted by mary- please check calculations. .
in testing a new drug. researchers found that 20% of all patients using it will have a mild side effect. a random sample of 14 patients using the drug is selected. find the probability that:
a) exactly three will have mild side effects.
b) at least four will have this mild side effect.
*once again the more i work with numbers the more i get confused. please show calculations in detail. thank you.