Publications by Quoc Tran
2020-01-03-Classic
Riddler Classic By Zach Wissner-Gross The New York Times recently launched some new word puzzles, one of which is Spelling Bee. In this game, seven letters are arranged in a honeycomb lattice, with one letter in the center. Here’s the lattice from December 24, 2019: The goal is to identify as many words that meet the following criteria: The w...
4066 sym R (6840 sym/20 pcs) 4 img
2019-12-20-Express
Riddler Express By Zach Wissner-Gross From Mark Hannan comes a holiday party stumper: You’re new at your job, and your office is voting on a theme for its holiday party. It’s fallen on you to record the percent of your coworkers (including yourself) who voted for each one. Well, since you’re in a hurry, you just write down everything in th...
1931 sym R (4491 sym/2 pcs)
2019-12-13-Classic
Riddler Classic By Zach Wissner-Gross From Steve Abney comes a particularly prismatic puzzle: Suppose I have a rectangle whose side lengths are each a whole number, and whose area (in square units) is the same as its perimeter (in units of length). What are the possible dimensions for this rectangle? Alas, that’s not the riddle — that’s ju...
3324 sym R (1878 sym/4 pcs)
2019-12-06-Express
Riddler Express By Zach Wissner-Gross For this week’s Express, I present an apparent coincidence that has bothered me since 2015: After being ambushed by the forces of the First Order on the planet Jakku, the droid BB-8 narrowly escaped and requires immediate help. Fortunately, there is one person (named Rey) on the planet who can help BB-8, b...
1145 sym
2019-11-22-Classic
Riddler Classic By Zach Wissner-Gross From Charlie Cordova comes a puzzle that brings logic and number theory to the lottery: Five friends with a lot in common are playing the Riddler Lottery, in which each must choose exactly five numbers from 1 to 70. After they all picked their numbers, the first friend notices that no number was selected by ...
2707 sym R (1522 sym/8 pcs)
2019-11-15-Classic
Riddler Classic By Zach Wissner-Gross From Ricky Jacobson comes a puzzle of seeing how low you can roll: You are given a fair, unweighted 10-sided die with sides labeled 0 to 9 and a sheet of paper to record your score. (If the very notion of a fair 10-sided die bothers you, and you need to know what sort of three-dimensional solid it is, then f...
1576 sym R (544 sym/3 pcs) 1 img
2019-12-06-Classic
Riddler Classic By Zach Wissner-Gross From Austin Chen comes a riddle of efficiently finding a song: You have a playlist with exactly 100 tracks (i.e., songs), numbered 1 to 100. To go to another track, there are two buttons you can press: (1) “Next,” which will take you to the next track in the list or back to song 1 if you are currently on...
6816 sym R (2775 sym/14 pcs) 5 img
2019-12-13-Express
Riddler Express By Zach Wissner-Gross From Anna Engelsone comes a riddle about a historic chess battle: The infamous 1984 World Chess Championship match between the reigning world champion Anatoly Karpov and 21-year-old Garry Kasparov was supposed to have been played until either player had won six games. Instead, it went on for 48 games: Karpov...
3701 sym R (3272 sym/7 pcs) 3 img
2019-12-20-Classic
Riddler Classic By Zach Wissner-Gross From Kathy Bischoping comes a question we’ve all asked ourselves at one time or another: I have 10 pairs of socks in a drawer. Each pair is distinct from another and consists of two matching socks. Alas, I’m negligent when it comes to folding my laundry, and so the socks are not folded into pairs. This m...
3249 sym R (2600 sym/6 pcs) 2 img
2020-01-31-Classic
Riddler Classic By Zach Wissner-Gross From Robert Berger comes a question of maximizing magnetic volume: Robert’s daughter has a set of Magna-Tiles, which, as their name implies, are tiles with magnets on the edges that can be used to build various polygons and polyhedra. Some of the tiles are identical isosceles triangles with one 30 degree a...
4101 sym R (565 sym/1 pcs) 6 img