Hi.
My name is Catalina Dragoi and I'm the mother of a six grader.

I have a question: how do you calculate the "positive difference between the GCF and LCM of two numbers"?

Thank you.
Regards,
Catalina

Hi Catalina,

You need to find the LCM and GCD of the numbers and then find the difference. I don't see any simpler way to do it. For example suppose the numbers are 210 and 300. First factor the numbers into their prime factors.

210 = 2 3 5 7
300 = 2² 3 5²

The GCD is 2 3 5 = 30 and the LCM is 2² 3 5² 7 = 2100 so the positive difference is

2100 - 30 = 2070.

Penny

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