- 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 349
__x 1001__ __x 1001__
abc 349
0 0
0 0
__abc __ __349 __
abcabc 349349

It is math Made Simple and Cool!

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