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Greatest common divisor

3 videos
1 skill
You know how to find factors of a number. But what about factors that are common to two numbers? Even better, imagine the largest factors that are common to two numbers. I know. Too exciting!

Greatest common factor exercise

VIDEO 6:50 minutes
Find the biggest number that will divide into the given 2 numbers. This is called the GCF or greatest common factor.No worries, we'll show you how to do it.

Greatest common factor explained

VIDEO 6:18 minutes
Here's a nice explanation of least common factor (or least common divisor) along with a few practice example exercises. Let's roll.

Greatest common factor

PRACTICE PROBLEMS

LCM and GCF word problems

VIDEO 8:34 minutes
Here we have a couple of word problems--one searching for the least common multiple and the other for the greatest common factor. Just read them with us slowly and follow along. You'll get it.