Which number is a common factor of 32,48,and 80?

Step-by-step explanation:

The GCF is found by listing the factors of all the numbers and picking the largest one that occurs in each.  The factors of your numbers are as follows:

32:  1, 2, 4, 8, 16, 32

48:  1, 2, 3, 4, 6, 8, 12, 16, 24, 48

80:  1, 2, 4, 5, 8, 10, 16, 20, 40, 80

Looking at those factors you can pick out anything you'd like:  all the common factors, the greatest common factors, whatever you need.

linear pair postulates