Probability ; Difficulty: medium How many balls in the urn? This week’s Riddler Classic is a statistical parameter estimation exercise. The Classic reproduced: This week’s Classic may seem nonsensical at
Probability ; Difficulty: hard Can you catch the Grasshopper? This week’s Riddler Classic features a grasshopper whose position on a log is only probabilistically determined (a quantum grasshopper?). The Classic
Pobability; Difficulty: easy A Sandy Puzzle The Riddler Classic from this week (Jun 3rd, 2022) at first glance might appear to be a geometry /alegbra/calculus problem; but is a straightforward
Pobability; Difficulty: medium How likely are you to win this game? The Riddler Classic from this week (May 13, 2022) is probability exercise involving tetrahedral dice. While the main question
Pobability; Difficulty: medium How many gems will you purchase to make it in this game? The Riddler Classic from this week (Apr 22, 2022) is probably an exercise of the
Logic; Difficulty: easy Can a leader get people to vote to make him(her)self richer? Puzzle worm Sandi Sandman sent me this simple yet interesting puzzle. Interesting because it offers a
Probability; Difficulty: easy Escaping the Eccentric Elevator I’ve adapted this probability puzzle from one that I came across some months ago. Edit: This submission also made to the FiveThirtyEight Riddler
Logic; Difficulty: easy Are you Mediocre Enough To Win? The Riddler Classic from this week is an easy but interesting game theory/strategy question that illustrates the idea of Nash Equilibrium.
Geometry, Algebra; Difficulty: medium Planetary Measurement The Riddler Classic from this week (Mar 25, 2022) is a geometry and algebra problem wrapped up as an astronomical measurements puzzler. As Star-vind
Probability ; Difficulty: medium The Riddler Express Mar 18 ’22: Is it Anyone’s Birthday This week’s Riddler Express deals with the age old “So whose birthdays are we celebrating on
Geometry; Difficulty: medium Geodesic on a cone The Riddler Classic from this week (Mar 4, 2022) is about the shortest path between points on the surface of a cone. Two
