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Puzzle #209: Can you work out how many houses there are on Long Road?

Can you solve this week’s arithmetical puzzle, Postman’s knock? Plus the answer to puzzle #208

15 February 2023

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#209 Postman’s knock

Set by Maslanka

There was a knock at Professor Numero’s door. It was a postal worker.

Excuse me disturbing you, but can you help? This letter has a cryptic address. I can’t make head or tail of it:

“To the Resident, The house with a number whose digits when multiplied together give five times what they sum to, Long Road”

The professor pondered. “Well, you’ve come to the right road. And, luckily, there’s only one house number in the road with this mathematical property – the one at the end, where Colonel Crypto lives.”

As you would expect,…

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