Question

I need help how to do these kind of problems...PLEASE

Participants in a study of a new medication received either medication A or a placebo. Make a tree diagram of the results of the study. Then find P(placebo and improvement).

Of all those who participated in the study, 85% received medication A.
Of those who received medication A, 67% reported an improvement.
Of those who received the placebo, 75% reported no improvement

Answer 1

Somebody please help me

Answer 2

I need to know the steps

Answer 3

Thanks campbell for helping

Answer 4

its a probability tree



to get the results change the percentages to decimals and multiply along the branch

so P( P and I) = 0.25 x 0.15 = 0.0375

or 3.75%

Answer 5

how did you get 0.15 for improve

Answer 6

@campbell_st

Answer 7

sorry it should be

0.15 x 0.25 placebo = 15% or 0.15 improvement = 25% or 0.25

the answer will still be the same.

Answer 8

I know .15 and 15% are the same thing, I want to know how you got it

Answer 9

well look at the information in the question

85% take the medication so 15% have to take the placebo

and for the placebo people is 75% show now improvement then 25% show improvement

Answer 10

How about the 23%