421.--A CHAIN PUZZLE.

[Illustration]

This is a puzzle based on a pretty little idea first dealt with by the

late Mr. Sam Loyd. A man had nine pieces of chain, as shown in the

illustration. He wanted to join these fifty links into one endless

chain. It will cost a penny to open any link and twopence to weld a link

together again, but he could buy a new endless chain of the same

character and quality for 2s. 2d. What was the cheapest course for him

to adopt? Unless the reader is cunning he may find himself a good way

out in his answer.

Amusements in Mathematics · 第 493 / 970 题