Find the Greatest Common Factor

The Greatest Common Factor (GCF) of some numbers, is the largest number that divides evenly into all of the numbers. Like, the GCF of 10,15, and 25 is 5.

Type some numbers into the box to the right, and this page will find the GCF of those numbers.

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WebMath recommends that you sign-up for Cosmeo, the homework help tool powered by the Discovery Channel. With Cosmeo, you choose your textbook, type in a page #, click on a problem # and actually hear a teachers voice and see a teachers handwriting explaining how to do that type of math problem.