Oh

Why are 1980 pennies worth more than 1979 pennies?

For the same reason that 10 pennies are worth more than 9 pennies.

November 21, 2008November 19, 2008 | Puzzles

The Mensa Diet

Finding himself hot and overweight at an Air Force base during World War II, Jerry Salny decided he could shed pounds by drinking scotch and soda. Here’s his reasoning:

It takes 1 calorie of heat to raise the temperature of 1 gram of water by 1° Celsius.
A glass holds about 200 cc of scotch, soda, and ice. Its temperature is 0° Celsius.
As he drinks the scotch and soda, his body must supply enough heat to raise 200 grams to body temperature, or 37°C.
That’s 200 grams × 37°C, or 7,400 calories.
“Since all the calorie books show scotch as having 100 calories per ounce, and none at all for the soda, we should be able to drink scotch and soda all day and lose weight like mad.”

“This has been tried,” Salny reported, “and although the experimenter hasn’t lost any weight in the process, he doesn’t worry about it much anymore.”

Why doesn’t it work?

	Select Click for Answer
There are two different calorie measures. An ounce of scotch contains 100 kilocalories, not 100 calories. So with each ounce he drank, Salny took in 100,000 calories and used up only about 1,000. Nice try, though.

November 16, 2008January 21, 2013 | Puzzles · Science & Math

The Pony Puzzle

pony puzzle

Sam Loyd claimed to have sold “one thousand million” of these puzzles in the late 1800s, but the solution requires an insight that most solvers overlooked.

“Cut out the six pieces very carefully, then try to arrange them to make the best possible figure of a horse. That is all there is to it, but the entire world laughed for a year over the many grotesque representations of a horse that can be made with those six pieces.”

	Select Click for Answer
“The black pieces of paper are nothing but a delusion and a snare. The pieces are placed to make a little white horse in the center as shown.”

November 9, 2008January 21, 2013 | Puzzles

The Trouble With Waistcoats

the trouble with waistcoats

Now, sir, your coat is off!
And see–
Your right-hand pocketed!
So let it be:
While o’er your arm
An endless string–
Some three yards round–
Hangs like a sling.
Take the string off–
But, just for fun,
It must be done
Keeping your right-hand in its place,
And not a smile must stir your face.
Until you find this puzzle out,
No coat shall wrap your back about.

How is it to be done?

	Select Click for Answer
“The string must be put through the armhole, and over the head, then through the opposite armhole; then the hand must be put up underneath the waistcoat, and the string drawn down around the body until the former drops down about the waist, when the experimenter may jump out of it and claim his coat.” From Dick & Fitzgerald, The Book of 500 Curious Puzzles, 1859.

November 6, 2008January 21, 2013 | Puzzles

“Who Can Tell?”

From Don Lemon, Everybody’s Illustrated Book of Puzzles, 1890:

Twice six are eight of us,
Six are but three of us,
Nine are but four of us,
What can we possibly be?

Would you know more of us?
I’ll tell you more of us.
Twelve are but six of us,
Five are but four of us, now do you see?

	Select Click for Answer
Letters.

November 1, 2008January 21, 2013 | Puzzles

Cube Route

What’s the angle between the yellow lines?

	Select Click for Answer
The simplest solution is to draw a third line: That creates an equilateral triangle — so the angle we sought must be 60 degrees.

October 27, 2008January 21, 2013 | Puzzles · Science & Math

Round Trip

A man eats breakfast at his camp, then travels due south. After going 10 miles in a straight line he stops for lunch. Then he sets out again due south. After going 10 miles in a straight line he finds himself back at camp. Where is he?

	Select Click for Answer
He’s anywhere within 10 miles of the South Pole, where these directions take him across the pole (“10 miles in a straight line”) and back again. See also Down, Over, Up.

October 22, 2008January 21, 2013 | Puzzles

“Grammatical Puzzle”

Let the rich, great, and noble banquet in the festal halls,
And pass the hours away, as the most thoughtless revel;
Then seek the poor man’s dreary home, whose very dingy walls
Proclaim full well to all how low his rank and level.

“Take away one letter from a word in the above stanza, and substitute another, leaving the word so metamorphosed still a word of the English language; and, by that change, totally alter the syntactical construction of the whole sentence, changing the moods and tenses of verbs, turning verbs into nouns, nouns into adjectives, and adjectives into adverbs, &c., and so make the entire stanza bear quite a different meaning from that which it has as it stands above.”

	Select Click for Answer
“Take away L in the subjunctive ‘Let’ at the beginning of the first line, and substitute S, and so turn it into the imperative ‘Set,’ when the changes which necessarily follow will be immediately apparent”: Set the rich, great, and noble banquet in the festal halls, And pass the hours away, as the most thoughtless revel; Then seek the poor man’s dreary home, whose very dingy walls Proclaim full well to all how low his rank and level. (As I read it, rich, great, and noble are now adjectives, banquet a noun, pass and seek second-person imperative verbs, thoughtless a noun, revel a verb, and all how low a noun phrase; away now means “apart,” rather than “freely,” and very is an adjective meaning “precisely.” The banquet is decadent, the home humble.) From Dick & Fitzgerald, The Book of 500 Curious Puzzles, 1859.

Click for Answer

October 12, 2008January 21, 2013 | Language · Puzzles

Varying Reports

Which statements on this list are true?

Exactly one statement on this list is false.
Exactly two statements on this list are false.
Exactly three statements on this list are false.
Exactly four statements on this list are false.
Exactly five statements on this list are false.
Exactly six statements on this list are false.
Exactly seven statements on this list are false.
Exactly eight statements on this list are false.
Exactly nine statements on this list are false.
Exactly ten statements on this list are false.

	Select Click for Answer
The statements contradict one another, so only one can be true. That means nine are false, so statement 9 is true. Adapted from a problem by David L. Silverman in the Journal of Recreational Mathematics, January 1969.

October 9, 2008January 21, 2013 | Puzzles

Strange Math

Two problems that will make you want to throw a chair at someone, from John Jackson, Rational Amusements for Winter Evenings, 1821:

If from six ye take nine, and from nine ye take ten
(Ye youths, now the mystery explain;)
And if fifty from forty be taken, there then,
Shall just half a dozen remain.

II.

One third of twelve, if you divide,
By just one fifth of seven,
The true result (it has been tried,)
Exactly is eleven.

How? Why?

	Select Click for Answer
I. $strange math solution$ II. One-third of TWELVE is LV, and one-fifth of SEVEN is V. And LV/V = 55/5 = 11. I warned you. See also A Universal Solution.

October 3, 2008January 21, 2013 | Puzzles