Participants in a study of a new medication received either medication A or a placebo. Find P(placebo and improvement).

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 a placebo, 62% reported no improvement...

Please help, I have absolutely NO clue how to go about this. Maybe walk me through it? I don't just want the answer, please.

Question

Participants in a study of a new medication received either medication A or a placebo. Find P(placebo and improvement). 

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 a placebo, 62% reported no improvement...

Please help, I have absolutely NO clue how to go about this. Maybe walk me through it? I don't just want the answer, please.

kropot72 · Answer

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@unnstability can you understand the above probability tree?

anonymous · Answer

Yes I can @kropot72

anonymous · Answer

Ultimately, what am I trying to find? The question says find P(Placebo and improvement) What does that mean? It doesn't make sense to me haha.

kropot72 · Answer

Good! Now can you calculate
$$\large P(placebo \cap improvement)=?$$

kropot72 · Answer

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Does this give you some understanding?