Numbers - General Aptitude

Q1:

768 x 768 x 768 + 232 x 232 x 232 = ?
768 x 768 - 768 x 232 + 232 x 232

A 1000

B 536

C 500

D 268

E None of these

ANS:A - 1000

Given Exp. = (a3 + b3) = (a + b) = (768 + 232) = 1000
(a2 - ab + b2)