For two positive integers a and b, if a*b*(a + b) is divisivble by 500 then what is the least possible value of a*b.
The two positive integers are:
a = 5 and b=15
5*15*(5 + 15) =1,500 mod 500 ==0
(a * b) = 5 * 15 == 75 - The least possibble value of a * b.