How to Calculate an Equivalent Fraction

By Bryan Keythman
Jupiterimages/ Images

Equivalent fractions are fractions that are equal in value, but have different numerators and denominators. For example, 1/2 and 2/4 are equivalent fractions. A fraction can have an unlimited number of equivalent fractions, which are generated by multiplying the numerator and denominator by the same number. The numerator is the top part of a fraction, and the denominator is the bottom part. To determine if two fractions are equivalent, cross-multiply the fractions--multiply the numerator of each fraction by the denominator of the other. The fractions are equivalent if the products are the same.

Determine a number to multiply the numerator and denominator of a fraction by. For this example, we will multiply the numerator and denominator of the fraction 3/4 by 3.

Multiply the numerator of the fraction 3/4 by 3: 3 times 3 equals 9.

Multiply the denominator of the fraction by 3: 3 times 4 equals 12.

Place the numerator over the denominator, which equals 9/12. This is equivalent to 3/4.