Fig and Pomegranate Trees

Difficulty: Medium · Topics: Discrete Mathematics, Sets, Word Problems

In a village there are 18 houses with at least one of a fig tree and a pomegranate tree in the garden, 15 houses with at most one of them, and 12 houses with exactly one of them.

What is the sum of the number of houses that have both trees in the garden and the number of houses that have neither?