Question

If 40% of the population owns a bike, 10% of the population owns a skateboard, and 5% of the population owns both, what percent of the population owns either a skateboard or a bike or both

Answer 1

45%

Explanation:

5% owns both so you remove that 5% from both the 40% and 10% because it's already in the "both" category. For example if Sara has both, then it also means that Sara is among the 5% that has both but also in the 40% that owns a bike and the 10% that owns a skateboard. You need to remove Sara from those two categories (skateboard and bike) because she's already in the "both" category.

So when you remove it, it's not 40 and 10 percent but 35 and 5 percent.

The answer is 35+5+5 = 45%