Math Riddles
Math riddles require that you dig into arithmetic and calculation a little bit to figure out the solution. These riddles rarely involve advanced trigonometry or calculus, but adding and multiplying is fair game.
Easy  
How can you place the numbers 1 through 9 in a 3x3 grid such that every row, column, and the two ...


Consider the following explanation for why 1=2 : 1. Start out Let y = x 2. Multiply through by x ...


In a bouquet of flowers, all but two are roses, all but two are tulips, and all but two are ...


Medium  
There are 1 million closed school lockers in a row, labeled 1 through 1,000,000. You first go ...


Using only and all the numbers 3, 3, 7, 7, along with the arithmetic operations +,,*, and /, can ...


Andy, Barry, and Carl race each other in a 100meter dash. They each run at a constant speed ...


Five coworkers want to know what the average of all their salaries is, but refuse to reveal ANY ...


The King of a small country invites 1000 senators to his annual party. As gifts, each senator ...


Hard  
Consider a 10character string consisting of the numbers 0 through 9, with each number appearing ...
