# Math Help - Probability word problem

1. ## Probability word problem

A company has developed a drug test to detect steroid use by athletes. The test is accurate 95% of the time when an athlete has taken steroids. It is 97% accu- rate when an athlete hasn't taken steroids. Suppose that the drug test will be used in a population of athletes in which 10% have actually taken steroids. Let's choose an athlete at random and administer the drug test.

Question:
(a) Suppose that the chosen athlete tests positive. What's the probability that he or she actually used steroids? Show your work.

2. ## Re: Probability word problem

Hey asilvester635.

If you haven't got the whole answer, can you calculate the probabilities P(Has Steroids|Positive Result), P(Has Steroids|Negative Result), P(No Steroids|Positive Result) and P(No Steroids|Negative Result)?