Sicherman Dice

Sicherman dice are a particular pair of six-sided dice that, when rolled, produce sums with the same probability distribution as a pair of standard six-sided dice. In other words, these dice do not have the arrangement of 1, 2, 3,…

Coin Rotation Paradox

The coin rotation paradox is a famous math problem with an unintuitive solution: If you roll a coin around the edge of another coin of the same size, from an external perspective, how many rotations does the coin make by…

Doubling Game

Three players gamble on a “doubling game.” In each round of the game, a single loser is determined, and this player has to double the money of the other two. After three rounds of this game, each player has lost…

Boy or Girl Paradox

The “boy or girl paradox” is a well-known brain teaser by famous puzzle-maker Martin Gardner. It’s popularly considered a “paradox” because (1) it has a highly unintuitive solution, and (2) its ambiguous wording meant either of two solutions could be…

Two Envelopes Paradox

The two envelopes paradox is a famous brain teaser of sorts, and not a true paradox. The problem is generally posed like this: You are given a choice between two identical envelopes. One envelope contains some amount of money, and…

Friedman Numbers

Friedman numbers are positive integers that can be written as an expression of its own digits and basic arithmetic operations. While Friedman numbers don’t have much practical use, they can be fun and creative puzzles for all ages! Rules of…

Honkai Star Rail Detector Thief

Honkai: Star Rail features a number of interesting logic puzzles in its quests. One side quest has you questioning suspects to determine the detector thief. Similar to some classic “who is lying” logic puzzles that you might have encountered before!…

Mystery Killer Riddle

A detective is called upon to solve the riddle of the mystery killer in a high-profile murder. There are only three suspects: The victim was holding a calendar, and it seems he marked several of dates before he passed away:…

5 Quant Brain Teasers

Whether you’re preparing for an interview or just trying to keep your mind sharp, here are some quant brain teasers to test your skills. Remember, if you get a brain teaser at an interview, you don’t necessarily need to get…