Wild About Math! Making Math fun and accessible


Monday Math Madness #5

Monday Math Madness!

Wow! We're on our fifth contest already! Time flies.

For this contest we have a new prize: The Art of Problem Solving folks have donated several $25 gift certificates that can be used in their bookstore. These folks do an outstanding job of challenging and inspiring kids to learn Math. Check out their website if you haven't already. I'll give away either one or two certificates, depending on how many correct solutions we receive.

This problem may be challenging for some but I encourage you to view this problem as an exploration and to look for patterns that will help you to solve it. I picked this exploration-friendly problem in honor of the folks donating the prize; Art of Problem Solving is all about Math exploration.

Here's the problem:

Aside from 1 and 9, are there any perfect squares whose digits are all odd? Justify your answer.

Here are the rules for the contest:

1. Email your answers with solutions to mondaymathmadness at gmail dot com.
2. Only one entry per person.
3. Each person may only win one prize per 12 month period.
3. Answer must be explained. You must show your work! Wild About Math! and Blinkdagger will be the final judges on whether an answer was properly explained or not.
4. The deadline to submit answers is Tuesday, May 6, 2008 12:01AM, Pacific Time. (That's Tuesday morning, not Tuesday night.)
5. The winner will be chosen randomly from all well-explained and correct submissions, using a random number generator.
6. The winner will be announced Friday, May 9, 2008.
7. The winner (or winners) will receive a $25 gift certificate, graciously donated by the Art of Problem Solving.
8. Comments for this post should only be used to clarify the problem. Please do not discuss ANY potential solutions.