Calculator Fun 1

by | October 27, 2016 | Math is Fun! | No Comments

1) Think of a two digit number
2) Multiply it successively by 3, 7, 13, and 37
3) What is the result?

For example you r two digit number is 97.

   97 x 3  = 291
  291 x 7  = 2037
 2037 x 13 = 26481
26481 x 37 = 979797

It is the same two digit number repeated three times!

Why does it work?

Since 3 x 7 x 13 x 37 = 10101, then any two digit number ab x 10101 = ababab

           ab	           59
      x 10101	      x 10101
           ab	           59
           0	           0
         ab  	         59
         0	         0
       ab    	       59    
       ababab          595959

That is Math, Simple and Cool!

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