- Think of a three digit number.
- Multiply it successively by 7, 11 and 13.
- What is the result?
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.
It is Math Made Simple and Cool!
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