3 Minute Challenge Puzzles are designed to develop speed and accuracy. There are six puzzles on a page and each puzzles is a series of interrelated calculations. Together these make the players brain get smarter at understanding and using basic mathematical operations. Today's world is increasingly mathematical. But we as a society are too dependent on hand held devices to do even basic calculations. People struggle with even simple problems because their brains are not just used to doing anything mathematical. These puzzles are a workout for the brain and a few minutes of these puzzles will provide a much needed exercise to your grey cells and boost your brain power. There are full solutions at the end of the book.