There is nothing better than a tricky brainteaser to test your intellect and satisfy your quest for new mental challenges. The search ends here, with this gold mine of the best, toughest, and most enjoyable math puzzles ever. Some use cards or marbles, others have diagrams, grids, and lively illustrations, still more present their questions as a story or riddle. Challenging Brainteasers
by Bernardo Recaman Santos