Reciprocal FractionsTo find the reciprocal of a fraction, flip it over, so that the numerator becomes the denominator and the denominator becomes the numerator. That is: The reciprocal of ^{4}/5 is ^{5}/4 Note that the product of a fraction and its reciprocal is always 1. ^{4}/5 x ^{5}/4 = ^{20}/20 = 1 In the case of a whole number, think of it as having a denominator of 1: The reciprocal of 5 is ^{1}/5. Every number has a reciprocal except for 0. There is nothing you can multiply by 0 to create a product of 1, so it has no reciprocal. Reciprocals are used when dividing fractions.
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