Quandaries and Queries



My name is Jerry and I am a math teacher at the secondary school level in the greater Toronto area. I posed the following problem to my enriched grade 10 math class that I found in the book called "Mathematics and the Imagination" by William Kastner. According to the author, it is posible for two people linked to each other with two ropes around their hands, to separate themselves without letting go of the rope. The students had lots of fun trying to accomplish this problem using skipping ropes from the Phys Ed department, but with no success.

Can you help me find a solution to this problem?



Hi Jerry,

I'm going to draw some diagrams, I hope they make sense. You have two people whith rope handcuffs that are linked. In my diagram one rope is brown and the other green and I only show one hand.

Take the green rope and under the brown rope at the wrist.

Take the green rope over the hand.

Slide the green rope under the brown rope so that it is over the wrist.

If you now lift the top piece of the green rope over the hand you will see that the handcuffs are no longer linked.


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