Your answer begins with your favorite number, followed by your age.

If you have had your birthday already in 2010: happy birthday and add 1 to the total. Choose your favorite number from 1 to 100. Think of these numbers as in a circle ( Diagram A), and going around that circle forever. How do I do it? The six fractions 1/7 to 6/7 have the same repeating sequence of six numbers after the decimal point, each fraction starting with a different number in the sequence 142857. Am I right? Now add up the first six digits after the decimal point. Is there a 1 somewhere after the decimal point? I predict that the number after the 1 is 4. (I’ll be nice and let you use a calculator, but you’ll need one that has at least seven decimal places.) If your total is a whole number (that is, no digits after the decimal point) divide the answer by 7 again. Choose a number from 1 to 70 and then divide it by 7. Benjamin shares some of the concepts from his DVD course “The Joy of Mathematics” and his book “Secrets of Mental Math: The Mathemagician’s Guide to Lightning Calculation and Amazing Math Tricks.”įollow the instructions below. dissertation, at Johns Hopkins, titled “Turnpike Structures for Optimal Maneuvers”: the maneuvers were inspired by a way of arranging Chinese checkers to move expeditiously across the board. When not amazing audiences around the country - squaring five-digit numbers in his head or guessing your number, any number - the Mathemagician is a professor of math at Harvey Mudd College in Claremont, Calif. Benjamin has two passions: magic and math.

7 times table up to 1000