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.
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.