How to Compare Negative Fractions

By Chance E. Gartneer; Updated April 24, 2017
Comparing negative fractions will be as easy as 2+2 if you follow a few simple rules, such as through cross multiplication.

Though comparing fractions can be confusing enough, bringing negative signs into the mix doesn't have to add to that confusion. Fractions are actually two stacked integers, with the one above the line called the numerator and the one beneath it the denominator. Numbers are negative -- and signified with a minus sign, or "-" -- when they are less than zero. Negative numbers work in reverse because as numbers increase their values lessen. You can compare the values of negative fractions with like and unlike denominators through the numbers appearing in the fractions.

Same Denominator

Find two negative fractions with like denominators for example purposes. For this example, let the fractions be -2/9 and -7/9.

Separate the numerators from the fractions. In this example, the numerators are -2 and -7.

Compare the numerators. The numerator that is greater in value indicates the greater fraction. Concluding this example, when comparing -2 and -7, -2 is greater than -7, so -2/9 is greater than -7/9.

Different Denominators

Find two negative fractions with different denominators for example purposes. With this example, let the fractions be -3/4 and -7/8.

Multiply each fractions' numerators by the others' denominators, assigning each fraction's negative sign to its numerator. In this example, multiplying 8 and -3 equals -24, and multiplying -7 and 4 equals -28.

Compare the two products from the previous step. If the product that includes the first fraction's numerator is greater than the other product, the first fraction is greater in value; if the product is less than the second one, the fraction is less in value; and if they are equal, the fractions are equivalent. Concluding this example, -24 is greater than -28; the fraction -3/4 is therefore greater than -7/8.

About the Author

Chance E. Gartneer began writing professionally in 2008 working in conjunction with FEMA. He has the unofficial record for the most undergraduate hours at the University of Texas at Austin. When not working on his children's book masterpiece, he writes educational pieces focusing on early mathematics and ESL topics.