At a certain health club, 30% of the members use both the pool and sauna, but 40% of the members who use the pool do not use the sauna. What percent of the members of the health club use the pool?
Is the answer 15?
Damn, took me too long to solve this, I am so out of practice.
The problem is actually pretty simple.
Let total number of members be X, set of members using the pool be P, and set of members using the sauna be S.
Then PS = 0.3X
Therefore 1/2 the members use the pool, as a percentage its 50%