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Fraction and LCD Guides

Clear explanations that complement the interactive calculators.

LCD basics

How to Find the Least Common Denominator

Learn the LCM, prime factorization, and multiples methods for finding the LCD of fractions.

Math concepts

Distinguish the least common denominator, least common multiple, and greatest common factor.

Fraction operations

See why unlike fractions need equal-sized parts before their numerators can be added.