0.875
The lowest term of 40 over 56 is 5/7
The lowest term of 66 over 168 is 33/56
14/25
16/56 = 2/7
56/72 reduces to 7/9
15/840 = 1/56
Find their GCF and divide them by it. 56/98 = 4/7
7/8
3/8
4/7
56 over 108 reduces to 14 over 27
It can be simplified to 5/8