Question

Problem Statement and Interaction Area... Problem attached in comments.

I know the answer, just not 100% sure how they got that, it's a practice test and I want to know how to do it for the real test. Thanks!

Answer 1

It's the ratio of headaches for Viagra to the ratio of headaches for Placebo, i.e.,: \[\huge\frac{\frac{hViagra}{nhViagra}}{\frac{hPlacebo}{nhPlacebo}} \]

Answer 2

Or, in other words, (113/625)/(24/703)

Answer 3

Thank you!!

Answer 4

No problem :-)