Source of Puzzles

A reader asked the other day where I got some of the puzzles I put on here. (Okay, she asked about two weeks ago, but I don't check the email all that often.)

Many of the roughly pre-calculus level math questions come from the UVM Math Contest. The website has only the last dozen years but I have the Notebook that goes back to the 70s.

Some of the Old-Timey one are from Sam Loyd's Puzzle Encyclopedia. You can find many of them on Wikipedia but I downloaded the images of the original book from mathpuzzle.com/loyd or get the whole thing as a zip file.

Word dominoes, of a sort

source: MENSA puzzle-a-day.

Holey Division Puzzle

Divide and Conquer 

Can you fill in the missing digits in the long division problem below?

ANSWER

src: Sam Loyd, 1914 E.o.P

Traffic Jam Wordsearch Puzzle

source: wpc

ANSWER

How many circles?

How many circles are visible or implied in this picture?

Source: wpc

ANSWER

Odd Man Out Puzzle

Source: Mensa cards.

ANSWER

Circles Puzzle

source: Will Shortz

ANSWER

Note: Mouseover the word to see the answer.

Coffee coupons

ANSWER

Presto Chango Puzzle

Answers

Rectangle of Squares Puzzle

Like this, with different side lengths.

"A perfect fit with no overlapping"

Take some squares as defined below and fit them into one big rectangle with no gaps or spaces between the squares or in the corners. (Using graph paper might make it easier.)

The squares have sides of the following lengths:
2, 5, 7, 9, 16, 25, 28, 33, & 36.

source: efriedman et al.

Painter's Puzzle

MOUSEOVER

FOR ANSWER

How many triangles

Hold your mouse over the image for the answer in slightly hidden form.

Pulley Puzzle

A puzzle by Harry Langman:
A thin belt is stretched around three pulleys, each of which is 2 feet in diameter. The distances between the centers of the pulleys are 6 feet, 9 feet, and 13 feet. How long is the belt?

from Futility Closet.

Film Alphabet "Puzzles"

From Steven Wildish's Friday Project: Film Alphabets.

There was no math warmup problem today. I put the 1990s up as the windows wallpaper and then turned on the SmartBoard. They were fascinated. It seemed a hit so I printed them out from the folder - in Windows, you can print some of the contents of a folder and it will automatically scale them to full-page -- and lined them up on the wall outside my door. Teachers thought it was a hoot. The person with the most solutions? The science teacher across the hall. The second best? A senior with a Netflix connection.

Feel free to put in some answers in the comments. The artist's website is cool too, but there are only solutions for the 80s and 90s up so far.

Very Difficult Treasure Hunt

A while back, I was floating around the web and found the following treasure hunt. I saved the images, and put a description and source into a Word document which has disappeared. If anyone can help, I'd appreciate it.

Who is responsible for this nasty, wonderful, complex, multi-layered, multi-disciplinary, I-Can't-Wait-To-Edit-It-and-Give-It-To-My-Own-Students puzzle?

Yes, it will take you a while.

Saturday Puzzle

Just thought I'd create the graphic for jd2718's question. The source of the puzzle is unknown to me but I'm sure that I've seen it before. The problem is simple ... given a square of side 1 and four circles each of radius 1 centered at the four corners of the square, what is the area of the "rounded square" in the middle?

For what it's worth, I got $1-\sqrt{3}-\frac{\pi}{3}$, but I can't follow all my scribbling to check it. Too much thinking for a Saturday afternoon.

The Trader's Puzzle - Balance Weights

What are the weights of the four rings to as to measure any desired weight from a quarter-pound up to ten, in quarter-pound increments?

Lake Puzzle

see the answer here.

Archery Puzzle

How close can the young archer come to scoring a total of 100 - using as many arrows as she pleases.
The rings are numbered 16, 17, 23, 24, 39, 40

Skating Puzzle

It is recorded that in a mile race between two graceful skaters the rivals started from opposite points to skate to the other's place of beginning. With the advantage of a strong wind Jennie performed the feat two and a half times as quick as Maude, and beat her by six minutes. The problem, which has created no end of discussion, is to tell the time of each in skating the mile.