- Think of a three digit number
- Multiply it successively by 7, 11 and 13
- What is the result?

For example, if your three digit number is 168

168 x 7 = 1176 1176 x 11 = 12936 12936 x 13 = 168168

It is the original three digit number repeated twice!

**Why it works**

Since 7 x 11 x 13 = 1001, then any three digit number abc x 1001 = abcabc

abc 349x 1001x 1001abc 349 0 0 0 0abc349abcabc 349349

It is math Made Simple and Cool!

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