17/63
85 over 102 in lowest terms = 5/6
102 over 170 in lowest terms is 51 over 85
In its lowest terms: 17/85 = 1/5
It's already in its lowest terms
17/20
55/85 = 11/17
85/100 = 17/20
5 goes into 55 11 times and it goes in to 85 17 times so 11/17.
17/85 = 1/5
17/20
85% = 85/100 = 17/20
It is 17/20.