One-Sided States

Only two U.S. state names can be typed with a single hand on a normal keyboard. What are they?

	Select Click for Answer
TEXAS can be typed with the left hand alone, and OHIO with the right.

November 27, 2006January 15, 2013 | Puzzles

A Weighty Problem

“Here is a quaintly told problem in mechanics, which, despite its apparent simplicity, is said to have caused Lewis Carroll considerable disquietude,” writes Sam Loyd in his Cyclopedia of 5000 Puzzles, Tricks, and Conundrums (1914). He quotes Carroll:

If, to a rope, passed over a loose pulley, is suspended a ten-pound counter weight, which balances exactly with a monkey eating an apple, swinging at the other end, what would be the result if the monkey attempts to climb the rope?

“It is very curious to note the different views taken by good mathematicians,” Carroll noted. “Price says the weight goes up with increasing velocity. Both Clifton and Harcourt maintain that the weight goes up at the same rate of speed as the monkey; while Sampson says that it goes down.”

So which is it? Be warned, Loyd’s thinking is inconclusive.

	Select Click for Answer
Lewis Carroll’s monkey puzzle is about as paradoxical as a recent conundrum which is going the rounds, as to what is it that will go down a chimney down, but will not go up a chimney up? (Umbrella.) There are three possible consequences to select from in the monkey problem: The progress of climbing might have no effect whatever upon the equilibruim; it might cause the weight to fall, which would raise the monkey quicker than he wished, or it might raise the weight, which would be apt to give the monkey a tumble. From the standpoint of a guess, pure and simple, opinions were about evenly divided, so two out of three were wrong in their conclusions. From a theoretical and scientific point of view it is just as paradoxical as the umbrella conundrum, for if the monkey goes up he will go down, whereas if he goes down he will go up. The argument is based on Newton’s law that “action is equal to reaction.” The engine which moves a train is pulling itself along by the rails. Theoretically speaking, if there was no friction, a fly could not crawl up that rope without destroying the equilibrium, so that the rope would be drawn over the pully and the monkey end fall by a rapidly increasing momentum. And there he leaves it.

Click for Answer

November 22, 2006January 15, 2013 | Puzzles

Desert Downpour

https://commons.wikimedia.org/wiki/File:Grifo_m%C3%A1gico.JPG — Image: Wikimedia Commons

A “magic tap” continuously fills a basin in El Puerto de Santa María, Spain. How is this possible?

	Select Click for Answer
The stream of water hides a pipe that supports the handle and drives the fountain.

Problem Solved

What happens when an irresistible force meets an immovable object?

It can’t happen. If a force is irresistible, then by definition there’s no such thing as an immovable object (and vice versa).

October 20, 2006October 17, 2006 | Puzzles

Zebra Puzzle

This puzzle has been attributed both to Lewis Carroll and to Albert Einstein:

There are five houses in a row. Each of the houses is painted a different color, and their occupants come from different countries, own different pets, drink different beverages, and smoke different cigarette brands.
The Englishman lives in the red house.
The Spaniard owns the dog.
Coffee is drunk in the green house.
The Ukrainian drinks tea.
The green house is immediately to the right (your right) of the ivory house.
The Old Gold smoker owns snails.
Kools are smoked in the yellow house.
Milk is drunk in the middle house.
The Norwegian lives in the first house.
The man who smokes Chesterfields lives in the house next to the man with the fox.
Kools are smoked in the house next to the house where the horse is kept.
The Lucky Strike smoker drinks orange juice.
The Japanese smokes Parliaments.
The Norwegian lives next to the blue house.

Who drinks water? Who owns the zebra?

Click for Answer

October 10, 2006January 15, 2013 | Puzzles

Diophantus’ Age

No one knows much about Diophantus, the Greek mathematician, but in the sixth century a math puzzle purported to give his epitaph:

“This tomb holds Diophantus. Ah, what a marvel! And the tomb tells scientifically the measure of his life. God vouchsafed that he should be a boy for the sixth part of his life; when a twelfth was added, his cheeks acquired a beard; He kindled for him the light of marriage after a seventh, and in the fifth year after his marriage He granted him a son. Alas! late-begotten and miserable child, when he had reached the measure of half his father’s [total] life, the chill grave took him. After consoling his grief by this science of numbers for four years, he reached the end of his life.”

At what age did he die?

	Select Click for Answer
He died at 84.

August 7, 2006January 15, 2013 | History · Puzzles · Science & Math

Unwanted

The maker doesn’t need it.

The buyer doesn’t use it.

The user doesn’t know he’s using it.

What is it?

	Select Click for Answer
A coffin.

July 26, 2006January 15, 2013 | Puzzles

The Kayaker

A child releases a toy boat in a stream that flows at 3 miles an hour. At that instant, a kayaker 14 miles downstream begins paddling upstream at 7 miles per hour. How long will it take him to reach the toy?

	Select Click for Answer
It will take 2 hours. We can ignore the speed of the stream, since it’s carrying both the kayaker and the toy. If he paddles at 7 mph, he’ll cover 14 miles in 2 hours.

June 27, 2006January 15, 2013 | Puzzles

Missing Square Puzzle

New York magician Paul Curry invented this puzzle in 1953. When the pieces of the triangle are rearranged as shown, suddenly a square is missing. How is this possible?

	Select Click for Answer
It’s not a true triangle — the hypotenuse is bent just slightly, by about 1/28th of a unit, to permit the deception. If you can’t see the bend, there’s another giveaway: If it were a true triangle, the red and blue pieces would be similar. But the blue triangle has a ratio of 5:2, and the red triangle has the ratio 8:3.

May 26, 2006July 18, 2013 | Puzzles

Cryptarithm

A “cryptarithm,” originally published by Henry Dudeney in the July 1924 Strand:

cryptarithm

Each letter stands for a different digit. Can you identify them?

	Select Click for Answer
O=0, M=1, Y=2, E=5, N=6, D=7, R=8, and S=9.

May 8, 2006January 15, 2013 | Puzzles