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Mysterious number 6174

Issue 38
in
  • 38
  • editorial
March 2006

Number guessing puzzles

The first beautiful puzzle was by Yukio Yamamoto in Japan:

If you multiply two five digit numbers you can get the answer 123456789. Can you guess the two five digit numbers?

If you multiply two five digit numbers you can get the answer 123456789. Can you guess the two five digit numbers?

And the second, very similar puzzle:

If you multiply two five digit numbers you can get the answer 123456784. Can you guess the two five digit numbers?

SOLUTION

The answers are:

123456789 = (3 x 3607) x (3 x 3803) = 10821 x 11409

and

123456784 =(2 x 112 x 43) x (23 x 1483) = 10406 x 11864

Go back to the hint | Return to the article

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