Question

how do you find pairs of numbers with a gcf of something? eg: "Find two pairs of numbers that have a GCF of 5."

Answer 1

Do you know what a GCF is?

Answer 2

yes.

Answer 3

Well, there are lots of numbers that this will work for. If you take 5 and any multiple of 5 it will work.

Answer 4

oh! so its just multiples?

Answer 5

It's kind of the opposite of multiples, but in order to find the greatest common factor, you use multiples.

Answer 6

Yeah I know that. I know how to find GCF's, but... yeah. okay, anyway, thanks.

Answer 7

Are you sure you understand? If you have a specific question, I'll do my best to answer it.

Answer 8

yeah, i understand.

Answer 9

thanks, though.

Answer 10

Multiply a bunch of primes together. Then multiply a bunch of different primes together. Then multiply each of these badass numbers by five, and BAM you have two numbers whose GCF is 5.

Make sure your primes are different though! With the exception that each is allowed to have a two, a three, or two twos.

Answer 11

Just kidding on that last part.