Question

For every positive integer x, let (xp) = (x - 1) + (x - 2) + (x - 3) + .... + (x - x). For example, (4p) = 3 + 2 + 1 + 0. What is the value of (500p) - (497p)?

A. 997 B. 1,490 C. 1,494 D. 1,497

Answer 1

500p = 499+498+497+497p

so 500-497p = 499+498+497 = 1494