Problem: Digital Multiplication

Here is another entertaining problem with the nine digits, the naught being excluded. Using each figure once, and only once, we can form two multiplication sums that have the same product, and this may be done in many ways. For example, $7\times 658$ and $14\times 329$ contain all the digits once, and the product in each case is the same — $4,606.$ Now, it will be seen that the sum of the digits in the product is $16,$ which is neither the highest nor the lowest sum so obtainable. Can you find the solution to the problem that gives the lowest possible sum of digits in the common product? Also, that which gives the highest possible sum?

Solutions: 1


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References

Project Gutenberg

  1. Dudeney, H. E.: "Amusements in Mathematics", The Authors' Club, 1917

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