Mental Math Challenges Author:Michael L. Lobosco ...guessing someone's age with just three simple questions; totaling up any five shopping items faster than a calculator; changing the color of a toothbrush in a flash. — You can do this and more -- with these colorful math challenges. All you need are some readily available materials, a sense of fun, and the desire to experiment. — Perform instan... more »t calculations and mind reading, vanishing tricks and illusions, precision measuring without instruments, and solitare pastimes. See how math works -- including why "Two Squares Always Make a Larger Square"; how you can "Solve Algebra Problems Instantly"; and ways to figure out the area of an unusual garden.
With just a little patience and effort, you'll solve every one of these challenges.« less