ShmoopTube

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Here's an unshmoopy question you'll find on an exam somewhere in life.

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If n is divisible by both 2 and 5, what is the remainder when n + 2 is divided by 4?

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And here are the potential answers.

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So, this question is asking us about remainders,

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or what's left over when we divide one number by another.

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Something neat we can do with remainders is that, if n is divisible by 2 and 5, we just

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multiply 2 and 5... and we know that n is also divisible by 10.

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Therefore, we know that n could be 10, 20, 30, 40, etc.

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and n + 2 could be 12, 22, 32, 42...

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The question asks us what the remainder is when n + 2 is divided by 4

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so if we just test the possible n + 2 numbers

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then 12 divided by 4 gives us 3 with a remainder of 0.

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22 divided by 4 gives us 5 with a remainder of 2.

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32 divided by 4 gives us 8 with a remainder of 0.

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42 divided by 4 gives us 10 with a remainder of 2.

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Looks like the remainder when n + 2 is divided by 4 is either 0 or 2.

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Our answer is E.

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As in, Egg salad sandwich.

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