10 minus 3 and 2/5 = 7 minus 2/5 = 63/5
9.9
It is: 63-4 = 59
63 minus 21 is 42.
The difference is 0. 0 cannot be represented by a normal power of 10, only as 10 to the power of minus infinity!
91 - 63 = 28
100 - 63 = 37
63 - 37 = 26
63 - 18 = 45
45 - 63 = -18
111 - 63 = 48
-16 - 63 = -79