Hey, Illinois Residents! Doctor E wants to visit your school! Have your teacher email doctore@math.uni.edu if you would like him to come by in May. Cooler than a field trip and cheaper than a movie!

Alas and alack, we have come to the end of another Wright Challenge! Every fortnight, the mysterious Doctor E supplies another puzzle for you to think about, and at the end of the semester, prizes of $60, $40 and $20 go to the top three finishers, with handsome certificates, suitable for framing, going to all sufficiently high-scoring finishers. Our friends at University Book and Supply will also be supplying boffo prizes. Eligible contestants include University of Northern Iowa students, Iowa high school students, and Illinois high school students.

Turning in the correct solution to this week's puzzle by December 24th will earn 2 puzzle points. A correct solution along with a good trivia question for me to use next year gets 3 puzzle points.

A magic square is a 3 x 3 array of numbers with the property that you get the same total if you sum up any row, any column, or even any diagonal. Here are some magic squares:

8
1
6
3
5
7
4
9
2
4
9
12
8
11
6
13
5
7

I have a 3 x 3 array of empty boxes, and some coins. I want to put the coins into the boxes in such a way that the total amount of money in each box forms a magic square. I have 5 quarters, 8 dimes, and 13 nickles.

a) Give me a way to do this that uses all the coins

b) Give me a way to do this using as few coins as possible (but at least one)

The deadline for sending in solutions has expired. But feel free to take some time to work on this one, and click here to see the answer. Alternatively, click here to see the current challenge.

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