To find the gcf, you must list the factors of both numbers, and whichever one is greatest, you would put on the outside. Like 16 is the gcf of 32 and 48, so that number remains on the outside. Now, for the inside numbers, 16 times what equals 32? 16 times 2. 16 times what equals 48? 16 times 3 equals 48. Put those in the parenthesis, and put an addition sign in between them.
