Question

What is the gcf of 56 and 12?

Answer 1

`4`

Explanation:

The Greatest Common Factor is the highest number that can be used to divide the two given numbers. It is easily found by writing down the factors of the two numbers and selecting the common one(s) which are the highest.

In the given examples, the factors of the two numbers are as follows:

`56: 2,2,2,7`

`12: 2,2,3`

Since there are two numbers common between the two sets of factors, the GCF is:

`2xx2=4`

Answer 2

4

Explanation:

Consider the Prime Factor Tree diagram below.

Observe that the common value (values that are in both) are 2 lots of 2. So the common factor is: `2xx2=4`

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`56 = 2xx2xx2xx7`
`12=2xx2xx3`