I agree 18
Each x and y are divisible by 3. Since they are consecutive multiples of 3 one of them is even (divisible by 2).
So x*y is divisible by 3*3*2=18
You guys are good at this kind of thing...i happen to solve it this way..
x = 3* m ( m=1,2,3,4,5,6)
y = 3 * n ( n=2,3,4,5)
Therefore xy /j = 9 mn /j ..
Any value of j MUST divide the smallest value of 9mn..which we get by plugging in the minimum possible value of m and n....that is.. m= 1, n =2.
We get ...18/j and the largest integer that can divide this is 18..
Think this is ok ?