Question

How do you find the greatest common factor of 80, 16?

Answer 1

The Greatest Common Factor of 80, 16 is 16

Explanation:

Method suggested :

• Find the prime factors of each number :

`80 = 2xx4xx10 = 2xx2xx2xx2xx5 = 2^4xx5`
`16 = 4xx4 = 2xx2xx2xx2 = 2^4`

• Find the common prime factors : in this case there's only 2
• If you have many, take the smaller of the exponents of theses common prime factors and multiply them together to find the GCF, for this example `GCF = 2^4 = 16`

Example : Find the GCF of 90, 24

`90= 9xx2xx5=3^2xx2^1xx5`
`24=3xx4=3^1xx2^2`

• The common factor primes are 2 and 3
• The smaller exponents of each are `2^1 and 3^1`
• Multiply those and the `GCF = 3^1xx2^1=6`

I hope that was clear, you can find more in the link below :

Source :
(http://www.coolmath.com/prealgebra/01-gcfs-lcms/02-greatest-common-factors-03)