Solution

(related to Problem: The Puzzle Wall)

The answer given in all the old books is that shown in Fig. $1,$ where the curved wall shuts out the cottages from access to the lake. But in seeking the direction for the "shortest possible" wall most readers to-day, remembering that the shortest distance between two points is a straight line, will adopt the method shown in Fig. $2.$ This is certainly an improvement, yet the correct answer is really that indicated in Fig. $3.$ A measurement of the lines will show that there is a considerable saving of length in this wall.

a192


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References

Project Gutenberg

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

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