# What is the probability a person’s cholesterol

1. Apr 8, 2012

### mcknia07

Took Drug Didn't Total
Cholesterol ≤ 200 60 50 110
Cholesterol > 200 40 50 90
100 100 200

We’ll call event A “cholesterol ≤ 200” and event B “took the drug”…..

What is the probability a person’s cholesterol ≤ 200? P(A)
What is the probability a person took the drug? P(B)
What is the product of these two probabilities (multiply the above together)?
P(A) * P(B)
Given that a person took the cholesterol drug, what is the probability that their cholesterol ≤ 200? P(A|B)
Does P(A) * P(B) = P(A|B)?
Are these events independent?
What does this tell us about the effectiveness of the drug?

2. Apr 8, 2012

### HallsofIvy

Re: Independent?

Good questions! Now, why did you post them here? If you want someone to do the problem for you, that isn't going to happen! And to get any help, you have to show us what you do understand about this problem and what you can do so we'll know what kind of help you need. You can do that by showing us what you have tried on it yourself. Or have you have not even tried to do this problem yourself?

3. Apr 8, 2012

### mcknia07

Re: Independent?

I posted in the wrong section.

4. Apr 9, 2012

### Staff: Mentor

Re: Independent?

This is the right section. What HallsOfIvy was asking was, what have you tried? If you don't show any effort at solving a problem you post, we won't help (see the Rules - https://www.physicsforums.com/showthread.php?t=414380).