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A quick question-Something that I learned that I forgot throughout the years.

If a question asked you for a multiple of 9 and 12, which would be less than 40, would "36" be an answer, as both 9 and 12 can multiply to get 36, yet it fits under the criteria for being under 40?

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up vote 5 down vote accepted

Yes you are correct with your reasoning. Multiples of $9$ are of the form $9m$ where $m \in \mathbb{Z}$, the set of integers.

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