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Two hundred patients suffering from depression enrolled in a clinical trial to test the effects of various antidepressants. Zoloft was given to 27% of patients, Lexapro was given to 30%, and Prozac was given to 27%. Thirteen percent were treated with at least Zoloft and Lexapro, 11.5% were given at least Lexapro and Prozac, 7% were given at least Zoloft and Prozac, and 4% were treated with all three drugs.
- (a) How many patients in the trial were given at most two of the three drugs?
- (b) How many patients were treated with Zoloft and Prozac but not Lexapro?
- (c) How many patients were given a placebo containing none of the three drugs?
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