## Regional Ratios

A regular hexagon and an equilateral triangle have the same perimeter.

A regular hexagon and an equilateral triangle have the same perimeter.

Did you know that there is a famous illusion associated with Lincoln’s “stove pipe” hat? The hat looks like it’s taller than it is wide, even when the height and width (including the brim) are the same. Let’s make a hat:

- Cut a circle with a radius of 5 1/2 inches.
- Cut a circle from the center of the first circle with a radius of 3 1/2 inches.

The smaller circle will form the tip of the hat, and what’s left of the larger circle will form the hat brim. If we had a rectangular sheet of paper of the right size, we could make the cylindrical part of the top hat.

Mia drew a shape with exactly 4 sides.

It has 4 lines of symmetry.

- Write 23 X’s on a piece of paper.
- On your turn you can erase or take away 1, 2, or 3 of the X’s.
- Turns alternate. You cannot skip your turn.
- The person who erases or takes away the last X wins.

I’ve always felt a connection to Punxsutawney Phil because my birthday is on February 2nd, the same day folks watch to see if Punxsutawney Phil sees his shadow! One year, I noticed:

- Phil’s height = 51.2 cm
- Suzanne’s height = 5′ 4″
- Suzanne’s shadow length at Gobbler’s Knob = 76.2 cm

Kelly was watching her favorite Winter Olympic event – the four-man bobsled. On each team a driver sits in front, followed by two teammates and the brakeman in the back.

The numbers 1 through 20 were assigned to the 20 athletes. The drivers wore numbers 1, 2, 3, 4, and 5.

Before the race Kelly studied the teams. Drivers 2, 3, and 4 were riding with brakemen 18, 15, and 20 respectively in three of the sleds. In another sled were 6 and 12, and in the remaining sled were 10 and 17.

Suddenly Kelly realized that if you added up the four numbers on each team, all five sums were the same!

At a recent math conference, lunch was provided for the participants. To be sure that there was enough food for everyone, the kitchen staff made more lunches than there were people attending. In fact, the ratio of prepared lunches to people was 7:5.

Because they anticipated a large number of vegetarians at the conference, the staff made 2 vegetarian lunches for every 3 non-vegetarian lunches.

It turned out that the ratio of non-vegetarians to vegetarians at the conference was 3:4.

Our son Specialist Lee Alejandre wished us a “Happy New Year!” from his Army post overseas using his iSight camera and iChat AV connection. It was 12:01 am, January 1, for us in Philadelphia, PA, but it was 2:01 pm for him in Seoul, South Korea!

My husband and I were talking about the time zones. I looked on the web and found that Philadelphia is about 203 degrees of longitude west of Seoul. Once we realized that there are 360 degrees of longitude and there are 24 hours in a day, we understood why there is a 14 hour difference in time.

We talk a lot about the problem-solving process here at the Math Forum and try to develop resources that will help teachers help their students get better at problem solving. We discuss how to encourage students to share their thinking (such as through Noticing and Wondering) and how to cultivate classrooms that value those thoughts and ideas as much as answers. But if we take a look at our own “problem solving” product, the Problems of the Week, we have to acknowledge that there isn’t so much support for process, starting with the “Compose Answer” button that appears at the bottom of each problem. Oops!

We have considered a number of possibilities, including an option (chosen by the teacher) to show just the scenario for a problem and then have fields in which students can submit their Noticings and Wonderings. That sort of thing would require some significant programming time, so while we are working on putting it in place (I’ll blog about it more before we get too far), we are first going to support the PoW process through some wording changes in the submission process. We’ve come up with some possibilities and wonder if anyone has alternative ideas.

On a problem page, it says, “Compose Answer”, which of course implies you have “an answer”. We’re thinking of changing that to “Submit Ideas”, which seems a bit more welcoming to submissions that might not actually contain an answer yet (or ever).

Once you get to the “submission” page, there are four spots we’re suggesting alternative wording:

**Original:**Credit for this problem will be given to ….**New:**Credit for these ideas will be given to ….

**Original:**Summarize your answer in a sentence or two**New:**Summarize your ideas in a sentence or two.

**Original:**Explain how you solved the problem. Include your math.**New:**Explain your ideas and how you figured them out.

**Original:**If you’ve created an image as part of your solution, you may upload it here.**New:**If you’ve created an image that illustrates some of your ideas, you may upload it here.

What do you think? Would these sorts of changes convey “process” to your students? Do you have any other suggestions?

During the February 26th MoMath Masters Tournament, @MoMath1 tweeted, “No googling – how many sides on an enneagon?” We thought, “Hey! We know enneagons!” If you don’t, maybe this scenario from a problem we first used in 1998 will give you some hints (as well as some ideas for something you could do with one).

Extend the sides AB and ED of the regular enneagon ABCDEFGHI until they intersect.

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