Yes, 18/42 = 9/21
three sevenths
13/21 can't be reduced.
21/40 cannot be reduced.
no 9 over 14 can't be reduced.
25/21 is already reduced to its lowest terms
18/42 = 9/21 = 3/7
736 and 21 are comprime so the fraction cannot be reduced.
The fraction 19/21 cannot be reduced any more.
It can not be reduced
No.
9/61 can't be reduced.