30 is the answer, I Hope this helped
Next time just look up
93 - 63 and it will automaticly pop up
It is: 63-4 = 59
63 minus 21 is 42.
93 - 89 = 4
584 - 93 = 491
93 - 15 = 78
47 - 93 = -46
100 - 63 = 37
111 - 63 = 48
45 - 63 = -18
-16 - 63 = -79
63 - 37 = 26
63 - 18 = 45