From Infinigons, etc: Putting myself in kids’ shoes You have a square dartboard. What is the probability that a randomly-thrown dart will land closer to the center of the dartboard than to an edge? Superb problem. I took the lazy route. … Continue reading
The newest car talk puzzler. Draw a diagram, it may help. Three men, Mr. White, Mr. Brown and Mr. Green, were in the habit of meeting in a local doughnut shop every morning for coffee and doughnuts. One morning as … Continue reading
New Math Puzzler up this week: Tommy’s Drive to Work RAY: Tommy has a new car, it’s 19 years old. … It has one of those newfangled six-digit odometers. It can register as many as 999,999 miles. So one fine morning last … Continue reading
Great article from the NY Times on the Danger of Praise, with an excellent puzzle included: Circle of Differences The numbers 1, 2, 3 and 4 are written at the corners of a large square. At each step, at the … Continue reading
Car Talk has a new math puzzler up that mixes math and science: There Was an Old Man…RAY: I’m going to recite an equation and, from that, you are going to give me a limerick that consists of five lines. TOM: Does … Continue reading
In Search of the Bogus Coins RAY: We have seven stacks of coins, each with 100 coins. Real coins weigh ten grams, and phony coins weigh 11 grams. We’re going to weigh the coins on an analytic scale, which works just … Continue reading
The Last Gasp of the Fiat “A car travels at a steady speed of 45 mph. Its fuel consumption is 30 miles to the gallon. It has a 15-gallon gas tank, which was full when the car started off. But at the … Continue reading
Excellent probability (ish) puzzler from Car Talk: Three Slips of Paper RAY: This is from Norm Leyden from Franktown, Colorado. The date on it is 1974–I’m a little behind. Three different numbers are chosen at random, and one is written … Continue reading
Puzzler 1: Every two-digit number can be represented as AB, where B is the ones digit and A is the tens digit. Right? So for example the number 43, A is 4 and B is 3. Imagine then that you … Continue reading
1. Cats, Dogs and Mice – Oh My! RAY: You’re given a hundred dollars and told to spend it all purchasing exactly a hundred animals at the pet store. Dogs cost $15. Cats cost a buck, and mice are 25 … Continue reading