# GCF and LCM

## LCM

LCM stands for Lowest Common Multiple, in other words, the smallest number that is a multiple of each number in a set of numbers.

LCM is helpful for many math operations, including finding a common denominator in fractions. The fastest and most efficient way to find a common denominator is to find the LCM of the denominators.

**How do you find a LCM?**

For many numbers, if you know your times tables, it's easy to figure out the LCM, it might even be obvious.

## GCF

GCF stands for Greatest Common Factor, in other words, the largest number that is a factor of a set of numbers.

GCF is helpful for many math operations, including simplifying fractions. The fastest and most efficient way to simplify a fraction is to divide the numerator and denominator by their GCF.

**How do you find a GCF?**

For many numbers, if you know your times tables, it's easy to figure out the GCF, it might even be obvious.