Calculator Fun 2

Try This

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

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.

a b c
x 1 0 0 1
a b c
0
0
a b c
a b c a b c
3 4 9
x 1 0 0 1
3 4 9
0
0
3 4 9
3 4 9 3 4 9

It is Math Made Simple and Cool!

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