It is: 18/90 = 1/5 in its simplest form
90/5 is 18/1 in its simplest form which is the same as 18
90/270 = (90*1)/(90*3) = 1/3
1/5
1/6
1 over 9
1/2
1/3
No but as 1/3 it is
1/15
1/15
1/4
18/90 = 1/51/5
1/5
1/31/3
Expressed as a proper fraction in its simplest form, by dividing the numerator and denominator by 4.5, 4.5/90 is equal to 1/20 or one twentieth.
1/4 is in its simplest form.