March 2010
9 posts
Switches
The warden meets with 23 new prisoners when they arrive. He tells them, “You may meet today and plan a strategy. But after today, you will be in isolated cells and will have no communication with one another.
“In the prison is a switch room, which contains two light switches labeled A and B, each of which can be in either the ‘on’ or the ‘off’ position. I am...
Yarr Maties
Five pirates discover a chest full of 100 gold coins. The pirates are ranked by their years of service, Pirate 5 having five years of service, Pirate 4 four years, and so on down to Pirate 1 with only one year of deck scrubbing under his belt. To divide up the loot, they agree on the following:
The most senior pirate will propose a distribution of the booty. All pirates will then vote, including...
The Oldest Plays the Piano
Two MIT math grads bump into each other while shopping at Fry’s. They haven’t seen each other in over 20 years.
First grad to the second: “How have you been?” Second: “Great! I got married and I have three daughters now.” First: “Really? How old are they?” Second: “Well, the product of their ages is 72, and the sum of their ages is the same as the...
The Rope Bridge
Four people need to cross a rickety rope bridge to get back to their camp at night. Unfortunately, they only have one flashlight and it only has enough light left for seventeen minutes. The bridge is too dangerous to cross without a flashlight, and it’s only strong enough to support two people at any given time.
Each of the campers walks at a different speed. One can cross the bridge in 1 minute,...
