PS Problem

If x and y are consecutive positive integer multiples of 3, what is the greatest integer J such that xy/J is always an integer?
a) 27
b) 18
c) 9
d) 6
e) 3.


xy/J always has to be an integer.

if you take 3 and 6, as x and y respectively and J as 27, xy/J wont be an integer.

J should be 3*6 for all other products of multiples to be an integer when divided by J.

Hope this clears your doubt..

Agree with Aks. IMO B. The example shown by Aks shows the reason why j has to be equal to 18?