# Take a 3 digit number and repeat its digits to make a 6 digit number. Now divide by 7, 11 and 13. What do you notice?

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Start with a three-digit number and repeat the digits to make a six-digit number, for instance 379379. Now divide by 7, then divide the answer by 11 and then divide this answer by 13.
What do you notice, does it always happen and what is the explanation?

posted Jul 10, 2017
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## 1 Answer

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Yes it does and we get initial number, see explanation below:
xyz xyz= xyz + xyz*1000= xyz*1001= xyz* 7*11*13 so when divided we get the initial three- digit number

answer Jul 11, 2018

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