
Power CardsA Mathematical Puzzle  Solution 
Choose a number from 131. Tell me which cards the number is in, and I can tell you the number. How do I do it? Find out below.





Let's say you pick 28. It is in cards 3, 4, and 5. Now look at those cards. Do you notice anything special? Add the first number of those three cards. Add 4 + 8 + 16. You get 28! What is so special about 4, 8, and 16?URL http://math.rice.edu/~lanius/pro/power2.htmlPowers of 2! Notice that the first number of all the cards is a power of 2. We can add powers of 2 and make any whole number.
Print this page and dazzle your friends by playing the trick with them. How to Create the Cards  Blank Cards
Power Cards Intro  Print Version  The Trick Explained  Blank Cards  Application  Binary Nos.
More of Cynthia Lanius' Math Lessons