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Greatest common factor

3 videos
2 skills
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. These are called the greatest common factors (GCF) or sometimes greatest common divisors (GCD). Yay, acronyms! Too exciting! Common Core Standard: 6.NS.B.4

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.

GCF and LCM word problems

PRACTICE PROBLEMS