Question

How many positive whole numbers less than or equal to 360 are divisible by 2 or 3, but are not divisible by 18?

Answer 1

You can do this through trial and error.

The answer is 260.

Explanation:

Off the bat, we know all even numbers are multiples of 2 so 180 numbers to be precise. Now we find how many even Numbers are divisible by 18 so all factors of 18 should be satisfactory so 18, 36 etc. there are 20 of those so 180 - 20 = 160

now multiples of 3. 360 dived by 3 is 120 - 20 =100, 100+160 = 260