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This discussion board is a place to discuss our Daily Challenges and the math and science related to those challenges. Explanations are more than just a solution — they should explain the steps and thinking strategies that you used to obtain the solution. Comments should further the discussion of math and science.

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## Comments

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TopNewestHint:Let $A$ and $B$ be the 2 integers. Show that $\dfrac A6$ and $\dfrac B6$ are coprime.Hint 2:Factorize $\dfrac{15120}{6\times6}$ into product of 2 coprime posiitve integers.Log in to reply

I have factorized 420 by 7 and 5 and then??

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We know that $A/6$ and $B/6$ are coprime positive integers, and that $A/6 \times B/6 = 420$.

So we want to find 2 coprime positive integers that give a product of 420.

For example $1\times 420$, $4\times 105$, $3\times35$, $15 \times 7$.

Is there any other way?

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$A$ and $B$ are divisible by 6, right?

BothAre there any other larger integer that must divide both $A$ and $B$?

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In other words, the largest integer that divides both $A$ and $B$ is....?

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420,4105,335,157 are the probable pairs.right??Log in to reply

$\quad \quad$

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