Balls and BoxesDate: 9/1/96 at 14:22:24 From: Anonymous Subject: Balls and Boxes Explain in detail how you can place 21 balls in 4 boxes so that there is an odd number of balls in each box. I came across this problem. No one in the class can find a solution. Is there one? If any two odd numbers make an even number, how can 4 numbers add up to an odd? Date: 11/05/96 at 19:59:13 From: Doctor Lynn Subject: Re: Balls and Boxes Your logic is quite right, but there is a (trick) solution. The answer to this old problem (which Doctor Jodi worked out) is that you put boxes into other boxes. For example, put seven balls into each of three boxes, then put these into the fourth box. It then contains 21 balls, which is an odd number! (groan) Hope that helps. :) Write back if you have any other questions you'd like us to answer. -Doctor Lynn, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
Search the Dr. Math Library: |
[Privacy Policy] [Terms of Use]
Ask Dr. Math^{TM}
© 1994- The Math Forum at NCTM. All rights reserved.
http://mathforum.org/dr.math/