CD’s on a Desk

A few weeks ago, I asked the students to figure out how many CD’s it would take to cover their four-desk pod. I didn’t tell them anything more than that.

How would you solve that problem?

I was very impressed with what I saw.

1. The questions: Do we need to cover the whole pod? Can they overlap? Can they hang off the edge? What if there are little bits of desk showing through? (Excellent questions because they all change “the answer”.)

2. The methods: All began by measuring their desks. Some chose to leave length and width separate, some chose to multiply into area. Some researched the dimensions of the CD and had to decide how they were going to use it.

3. The answers: There were several recurring ranges of answers, but in terms of the numbers, there were probably 15 different final answers and the students were okay with that considering the assumptions were different.

All of that reflects a TON of great math thinking and problem-solving, but the most convincing solution to many of the students was arguably the simplest. (Isn’t it always that way?)

Here is a photo of the solution:

Photo Credit: Heather Roadcap – Used with permission

The solution: Get a CD, trace it carefully, and count. Can you argue with that?


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s