The number of positive integers that are less than 500 and that are not divisable by 2 or 3 is?

Question

There are 250 divisible by 2, 166 divisible by 3 and 83 divisible by both. So 250 + 166 - 83 = the numbers divisible by 2 or 3, without double counting. Subtract that number from 500.

How did you get 83?

That's the number of positive integers less than 500 divisible by 2 and 3. If you don't subtract that number out, then you'll double count them since they are already included in the counts of both multiples of 2 and 3.