![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
Greatest common factor (GCF) is a factor that is greatest among the
\common factors of the numbers.
\List the factors of each number.
\Factors of 27: 3, 9, 27
\Factors of 45: 3, 5, 9, 15, 45
\Factors of 90: 2, 3, 5, 6, 9, 10, 15, 30, 45, 90
\Identify the greatest common factor.
\The greatest common factor of 27, 45 and 90 is 9.![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
The greatest common factor of 27, 45 and 90 is 9.