How many positive integers divide evenly into either 144 or 196 but not 72?
1 - 144 mod 16==0, 144 mod 48==0, 144 mod 144==0. None of these numbers divides 72 evenly.
2 - 196 mod 7==0, 196 mod 14==0, 196 mod 28==0, 196 mod 49==0, 196 mod 98==0 and 196 mod 196==0. None of these numbers divides 72 evenly.
