it is in simplest form
31 and 61 have no common factor, so 31/61 can't get any simpler than it already is.
34/61 is in its simplest form.
61/72 is in its simplest form.
61/200 is in its simplest form.
31/4 is in its simplest form.
Since the numerator of the fraction is prime, the proper fraction 61/102 is already expressed in its simplest form.
32/61
61/128
31/16 is in its simplest form.
9/31 is in its simplest form.
31/36 is in its simplest form.
13/31 is in its simplest form.