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Number 1089

28 November 2:00 am
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Number 1089 is a centerpiece of a curious mathematical trick.

Take any 3-digit number, say, 732 and write it backwards: 237 in this example. Now, subtract the smaller of the two numbers (237) from the larger number (732).  The answer is 495.  Write this one backwards too and compute the sum: 495 + 594.

Here comes the surprise: regardless of your original selection, the final result will always be 1089!

Go to Why the Answer Is Always 1089 to learn why this is so.

How fun!  And fun learning is forever learning!

Ann Simpson

By the way, this is just one of the interesting bits of information in the FREE Math Tutoring Book I wrote about last week–http://i-a-e.org/free-iae-books.html.

This trick does not work if the number is a palindrome — that is, if the number is the same when it is written backwards.

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