If m=6 mod 9 and n=0 mod 9 , then what is the largest integer that mn is necessarily divisible by?
Changing them to mod 10
m=9a+6=3(3a+2)
n=9b=3×3b
a and b are integers.
It is possible that n is 0 all (any mod) but if it is not the answer is 3.
The answer isn't 3.
PS, the recapcha thing validiator is so annoying!
m = 3s, n = 9t, so mn = 27st will be divisible by 27.
THANKS!
it's correct :)
Nice work guest :)
+48 
