This box is
the eighteenth in a series
of letterboxes with mathematical clues. The boxes are intended for both regular
letterboxers and my students. This box was created for my 2005 Advanced
Algebra for Freshmen class for extra credit. Since Mathman 2 is dangerous
to do during winter, I wanted to have an alternative matrices letterbox for them
to do at the end of the first semester. As such, this box is very winter
friendly, with most of the "grunt work" done indoors. Once you decode the
clues, it shouldn't take more than 20 minutes outside to find the box, stamp up,
and return to the car. The indoor part however, may take a couple of hours
as it may take some time to find the numbers you need and then to decode the
These clues rely heavily on the use of matrices to encode/decode clues. Go
to this page to learn
how to do this on a free graphics calculator simulator or to do it by hand.
Be sure to read through
all the clues before looking for the box so you know what is expected of you.
Go to the Old Courthouse Museum at 320 S. 5th Avenue in West Bend, WI.
There is parking in the back, but you must enter off of Chestnut. The main
museum is free, but there is a donation box if you care to contribute.
There is a fee to see the jailhouse, but this letterbox doesn't require you to
go through the jailhouse. You might also want to check out the art museum
across 6th Ave. as well, especially to do Mathman 23).
Entrance to the Old Courthouse Museum is in the front.
You can go here to check when the
museum is open. When I went during operating hours, the door was locked,
but the staff opened it after I knocked, so don't give up if you find it locked
I wanted people to tour around the museum to collect various
bits of information to be used to decipher the matrix clues, but the museum
changes the exhibits more than I anticipated. Therefore I am including
photos of the exhibits I found to make the clues. Just click on the links
in the clues below. You can use them to solve the box. I would still
encourage you to visit on your way to the box. If you find a problem, please let
Find the math textbook that is open to "Chapter VI: United States Money and
Other Decimals." Read about US money and mills. Although this
textbook is old and you don't hear much about mills in school anymore, mills are
still used in various industries! In fact, there is one case where you run
into the use of mills almost on a daily basis because the industry is forced to
force them on you by law. Think, where do you see mills used in a posted
Now that you've read the lesson, here's some homework to do:
Find how much money you would have if you added the
2 dollars 8 cents 3 mills
1 dollar 9 mills
Take the four digits of your answer and place one each in
the following (de)coding matrix to decode the first message (Ignore decimals.).
Always write the message in the space provided at the end of the clues.
Probably one of the coolest exhibits in the museum is the 1913 Harley
Davidson 9G Forecar. Of the 6732 9E's made in 1913, how many were
into 9Gs? ______ This will be the first two digits used in the matrix
below. To get the other two, look around and find the
price of gasoline
"to-day": ____ cents! Now rev up your engines and decode away!
I've heard of bottled water, but canned water???!!! Why would they
What year is the canned water from? ______
From water to beer. What year did Geotter begin commercial brewing in West
Enter the four digits of the canned water year as the four exponents in
the numerator of the following problem (fill in the 4 blanks). Then reverse the order of the four
digits of the brewery year and place them as the four exponents in the
denominator of the following problem:
Simplify the expression (remember, no negative exponents allowed!). Enter
the four exponents in the simplified answer as the four numbers that make up the
next (de)coding matrix:
Even Lewis and Clark used expensive "Mathematical Instruments". How
expensive was their most expensive "Mathematical Instrument" the
_____ (Makes you think graphic calculators are cheap!)
They traveled under a different flag than we do today.
How many stars were on the flag they would've taken (see flag replica)? _____
Multiply these two numbers together to get a four digit
number, and enter each digit into the (de)coding matrix below and decode the
Find the Self-winding Clock and read about this interesting timepiece.
Write the four digits of the year the company was formed in New York into the (de)coding
matrix and decode the message:
Find the picture of the "Spirit of Washington County Wisconsin" and read
about its history. Take the year the savings bonds were collected in
______ minus the number of "minute men" that helped collect the bond money
_____. What is your four digit result? _______ Enter these four
digits into the following (de)coding matrix and decipher the clue!
The room about the ancient Indians of Wisconsin and Washington county is
very informative. Take time to listen to the Indian music while reading
about the effigy mounds at the nearby Lizard Mound Park. If you are
visiting during non-winter months, you might want to take a trip to the park to
experience the mounds yourself! (You'll never know what interesting things
you might find there if you look in the right spots!)
Did you know that Black Hawk led his people through Wisconsin? If you
browse The Story of Wisconsin Indians you can find the year of
route through Wisconsin. Enter the four digits into the (de)coding matrix
below to get another clue!
Each of the
determinants you calculate below are two digit numbers, so you
will have four digits to enter in the (de)coding matrix below. Put
them in in the order you have them into the (de)coding matrix, keeping the negative sign with the
digit that it is in front of.
In what year would you find a prayer book in a ladies' bag?
Put the digits of this year in the following matrix and find its
In what year would you find an MP3 player in a ladies' bag? _________
Put the digits of this year in the following matrix and find its
Find out what a "beetle" is used for:
What year is the "beetle" displayed from? ______
Also, there is a neat hitching post that used to be in front of a
office on _____ Poplar St.
Take the "beetle" year and add it to the doctor's street number and you get:
Enter these four digits below and decode the following
without a hitch!
Did you know that at one time, Washington and Ozaukee Countries were
divided east-west instead of north-south! The old map of the counties isn't that
old however. The date on the map does however look like a subtraction problem,
so do the math and enter the four digits into the following (de)coding matrix to
finish the clues!
To find the box, write the decoded texts on the corresponding lines below.
Then follow the clues!
Clues to the box:
Go to Ridge Run Park.
Enter just north of UWWC off University Dr.
Park in lower lot.
There you will find a large fallen tree or branch. One of
its broken arms is sticking up at you about waist high about six feet from the
back of the tree. The box is hiding in one of the various cavities of this
branch. Remove the loose bark in the cavity of this arm to
find the box. After stamping up, replace the box and the loose bark so the box
canít be seen, but make it look natural.
BEFORE RETRIEVING THE BOX, BE SURE NO ONE IS AROUND TO SEE YOU TAKE THE BOX
OUT! DO NOT BRING ATTENTION TO YOURSELF OR THE HIDING LOCATION OF THE BOX!
Before you set out read the
responsibility and disclaimer.