Mental Floss

Time for Some Mental Hygiene: It's the mental_floss Weekly Puzzle

By Editorial Staff

Cat videos are cool and all, but the next time you’re in need of a mid-day pick-me-up, consider something slightly more stimulating: our weekly brain teaser, created by the late, great mathematician and puzzle master Martin Gardner. This week, it’s up to you to figure out how many links you must cut in order to weld a bracelet together.

Once you've worked out a solution, scroll down to see if you're right.

From My Best Mathematical and Logic Puzzles, Martin Gardner, 1994, Dover Publications, Inc. Buy at Amazon.


You have taken up the hobby of jewelry making and you want to join the four pieces of silver chain shown at the left to form the circular bracelet shown at the right. Since it takes a bit of doing to cut open a link and weld it together again, you naturally want to cut as few links as possible. What is the minimum number of links you must cut to do the job?


It is only necessary to cut the three links of one piece. They can then be used to join the remaining three pieces into the circular bracelet.