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## Comment on

GCD of x and y is 12## Why couldn't the answer be 48

## Keep in mind that we're

Keep in mind that we're looking for an answer choice that MUST be true.

If the greatest common divisor of x and y is 12, then it COULD be the case that x = 12 and y = 12

If x = 12 and y = 12, then 2x = 24 and 2y = 24, and the greatest common divisor of 24 and 24 is 24.

So it need not be the case that the GCD is 48

## Hi Brent, is it least common

## Good catch! I meant to say

Good catch! I meant to say GREATEST common divisor. I've edited my comment above.

Thanks for the heads up!

Aside: The least common divisor of ANY two positive integers will always be 1.

## Thanks Brent!!