Calculator Fun 2

by | November 03, 2016 | Math is Fun! | No Comments
  • 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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