## Brain Teaser

Question This two-player game begins with 10 stones laid out in a row. The players take turns removing stones from the row.

SolveQuestion Starting from the same spot at the same time, Usain and Tyson run around a circular track in opposite directions. Usain r

SolveQuestion Veera and Emmi each live on the same floor of neighboring buildings and their windows are at a height of 6.25 m. Veera ac

SolveQuestion Every letter shown corresponds to a different digit. What is the sum A + R + E? 12 14 16 18

SolveQuestion The fractal shown is made up of infinitely many triangles with their bases on the number line between 0 and 1. Wit

SolveQuestion One, two, three, four… A waterdrop falls from a skyscraper’s balcony every 0.5 s. The first drop hasn’t

SolveQuestion The semicircle has the right triangle’s hypotenuse as its diameter. The radius of the quarter-circle equals a leg l

SolveQuestion The title of Brilliant’s Problem Solver of the Year has been narrowed down to five candidates: Katherine J., Muhamm

SolveQuestion Gracie plays a game where she spins arrows around the two circles below. The circle on the left is divided into four sect

SolveQuestion In this game of Nim, Abdi and Suri are playing with one heap of 11 stones and another heap of 9 stones. The game is playe

SolveQuestion To celebrate the end of exams, three couples met for a dinner. They’re about to take seats at a round table for six

SolveQuestion This figure includes 20 line segments. Using these rules: you can start at any intersection on the figure, you can

Solve