Simplifying Complex Fractions (multiplying by common denominator) Method 1: This is one of two methods for simplifying complex fractions.To Simplify a Complex Fraction by Multiplying by a Common Denominator. 1. Find the least common denominator (LCD) of all fractions appearing within the complex fraction. 2. Multiply both the numerator and the denominator of the … [Read more...] about Simplifying Complex Fractions (multiplying by common denominator)