![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
Method 1:
\Factor the each monomial.
\4st = 2 · 2 · s · t.
\10s = 2 · 5 · s.
\The GCF is the product of the common prime factors in each monomial.
\GCF = 2 · s = 2s.
\The greatest common factor of 4st and 10s is 2s.![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
The greatest common factor of 4st and 10s is 2s.