Car Talk Annulus Puzzler

Awesome! RAY: This puzzler is from a fellow named Jerry Olsen. Ed and his two sons, Biff and Skip, have been hired to paint the floor of a merry-go-round. They want to make sure they measure the floor area exactly, because they don’t want to buy any extra paint. The carousel, of course, is a […]

Four and Five – Cartalk Puzzler

From cartalk. Ray: Get a piece of paper and write the number four, leave a little space, and write the number five. What common mathematical symbol, when placed between the numbers four and five, will result in a number that is greater than four but less than six? Tom: It has to be a mathematical […]

Fermat Was Wrong? Puzzler

From Car Talk. RAY: Here it is. Everyone, almost everyone remembers from his or her days in school the Pythagorean Theorem. TOM: Yes. RAY: A squared, plus B squared, equals C squared. And there are numbers like three, four and five; five, 12, 13 which satisfy that little equation. And many hundreds of years ago […]

Break a Weighing Stone

From the weekly car talk puzzler: RAY: A farmer had a 40-pound stone which he could use to weigh 40 pounds of feed; he would sell feed in 40 pounds, or bales of hay, or whatever. He had a balance scale; he put the stone on one side and pile the other side with feed […]

Painting Puzzler – Car Talk

I never could remember how to solve these type of questions. RAY: Tommy, Dougie and I are sitting around the office one day at Car Talk Plaza. We were noticing how dingy the place looked. We’d been there 15 years, and the place had never been painted. So, we decided to paint Car Talk Plaza. […]

First Day Activity: Puzzlers

On the first day of class in AP Calculus and Pre-Calculus Honors I’ll give out the following list of puzzlers that they’ll have a limited amount of time to work on. The students will be working in groups on the new $2 interactive whiteboards. Google Doc link. PDF link. Btw, I still haven’t figured out […]

The Love Tree – A Math Puzzler (?)

From Car Talk. A teenage boy smitten with a teenage girl in his high school freshman class, made his feelings known. Overjoyed at finding them reciprocated, he took pen knife to a young hard wood in the vicinity and carved their initials within a heart, five feet up the tree’s trunk. By their senior year, […]

Dr. Square

Much like the Collatz conjecture, the Dr. Square Puzzle (from the blog mathforlove) is an intriguing problem. With some playing around, we came up with what I think is an excellent (and solvable) puzzle. He dubbed it the Dr Square puzzle, because it involves one of the steps in taking the digital root (dr) and squaring numbers. Here’s how it goes. […]