Question

What is the GCF of 30 and 45?

Answer 1

15

Explanation:

'Splitting' the numbers down into their prime factors giving:

`30-> 2xxcolor(red)(3)color(white)(xx 3)xxcolor(blue)(5)`
`45->color(white)(2xx)color(red)(3)xx3xxcolor(blue)(5)`

The common values are: `3xx5=15`

So the GCF = 15

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
You will find a list of prime numbers on any search engine. I would suggest that 'images' may be a better search option.