60 + (-57) = 3
-32
37
Add any number to (60 minus the same number).
Well, the numbers between 55 and 60 are:56575859And if you then add 5 and 8 they make 13 so the number is 58.
-77
-15 and 4 Proof; -15 x 4 = -60 -15 + 4 = -11
62
1660
64
5 and 12
60
unfactorble i think