17 over 105 already is in simplest form. Because 105 is not divisible by 17, and 17 is only divisible by itself and 1, you are left with the original fraction.
7/17 is already in its simplest form
17/12 is the simplest form.
17/100 is in its simplest form.
17/32 is in its simplest form.
17/45 is in its simplest form.
12/17 is in simplest form.
17/50 is in its simplest form.
17/27 is in its simplest form.
17/14 is in its simplest form.
17/13 is in its simplest form.
17/80 is in its simplest form.
17/20 is in its simplest form.