The sum of all positive integers less than 300 which are not divisible by 3.
Please help!
The sum of all positive integers from 1 to 299:
299 x 300/2 =44,850
The sum of all positive integers less than 300 and DIVISIBLE by 3:
=n/2[2a + (n - 1)d]=99/2[6 + (99 - 1).3] =14,850
The sum of all positive integers less than 300 and NOT divisible by 3:
44,850 - 14,850 = 30,000.
