Which of the following is not equivalent

90/139 is the only fraction not equivalent to 45/70.

To find if a fractions are equivalent, divide the numerator by the denominator for each fraction.

45/70=0.642857
27/42=0.642857
9/14=0.642857
63/98=0.642857

Notice how all of these get you the same number. However, when you divide 90 by 137, you get 0.64748, which is not the same as the others. Therefore, 90/137 is the fraction that is not equivalent to 45/70.

45/70= 9/14 (divide by 5) 27/42= 9/14 ( divide by 3) 63/98= 9/14 ( divide by 7) 90/139 does = 9/14 and is NOT equivalent hope this helps

We need more info then that