Riddler Puzzles

The end of daylight saving time here on the East Coast of the U.S. got me thinking more generally about the calendar year. Each solar year consists of approximately 365.24217 mean solar days. That’s pretty close to 365.25, which is...

The Riddler Shirt Store sells N kinds of shirts, each kind with a picture of a different famous mathematician. Unfortunately, on average, 80 percent of orders are returned. That’s because the company’s website has customers order their shirts using a code (from...

Two ants named Geo and Desik are racing along the surface of a cone. The circular base of the cone has a radius of 2 meters and a slant height of 4 meters. Geo and Desik both start the race on the...

From ​​Travis Henry comes some vehicular trouble: You want to change the transmission fluid in your old van, which holds 12 quarts of fluid. At the moment, all 12 quarts are “old.” But changing all 12 quarts at once carries...

Amare the ant is traveling within Triangle ABC, as shown below. Angle A measures 15 degrees, and sides AB and AC both have length 1. Amare starts at point B and wants to ultimately arrive on side AC. However, the...

Trig the turkey cannot fly. And so, instead of flying, he decides to jump as far as he can with a running start up one of the famed Sinusoidal Hills, all of which are precisely the same size. Trig knows...

Can You Stick It To The Genie?