Question

Participants in a study of a new medication received either medication A or a placebo. Find P(placebo and improvement). You may find it helpful to make a tree diagram of the problem on a separate piece of paper.

Of all those who participated in the study, 80% received medication A.

Of those who received medication A, 76% reported an improvement.

Of those who received the placebo, 62% reported no improvement.

I don't know how to do this at all, any hints or help would be nice. :)

Answer 1

Did you ever get it?

Answer 2

participants—80% Medication A-----76% improvement
24% no improvement
20% placebo-------38% improvement
62% no improvement
20%*38%=.2*.38-7.6%

Answer 3

Thanks for this! Remember, it's not cheating unless you're caught.