4/77 is already simplified.
12 over 63 simplified = 4/21
If you mean 63/77 then it is 9/11 simplified
54/63 = 6/7 simplified
63/64 cannot be simplified further.
6/63 = 2/21 simplified
45/63 is 5/7 simplified
It is: 63/60 = 21/20 simplified
The simplified fraction of 15 over 63 is 5/21
24/77 cannot be simplified any further
2/63
41/63