Sunday, September 14, 2014

My Brilliant Husband - The Artist (Mathematician)

A great friend of mine (who is a math specialist in a school district) and I met late last week for lunch. During our visits, we often discuss different mathematical problems and new things we have learned along the way. This time was no different. After getting caught up a bit, Jenny asked me about a problem she had seen where people were asked to mentally do the problem 600 ÷ 48. Jenny explained that in what she read, there were 3 common ways that folks attacked that problem. How would you do 600 ÷ 48 mentally? What answer do you get? How do you get it?

True confessions....that one stumped me. It wasn't that I couldn't get it, but on-the-spot pressure blocked me from moving forward. I knew 10 something or other.

Jenny shared with me 3 common ways that people approached this problem mentally that were mentioned. There are a ton more, but these the three methods below were mentioned in the book. 
600 ÷ 48 
  • Think of the problem as 100 ÷ 8
  • Think of the problem as ½ of 100 ÷ 4
  • Think of the problem as 600 ÷ 50 + ½
For the first problem, Jenny and I agreed that was easy to figure out.....make it a simpler problem by dividing both 600 and 48 by 6. Now your problem is 100 ÷ 8. And if you know that you can do that and not change the value of the solution, it is easier to do 100 ÷ 4 first and simply take half of your answer. But the last one....hmmmmmm.

Is 600 ÷ 50 an easier problem, sure. That gets you an estimate but where does that darn + ½ come from? I wanted to be able to provide Jenny with a visual model of what that might look like because to be honest, if we could figure that out, it would make it a much much easier mental math problem.

The next morning while my husband David and I were walking. I was thinking out loud and said "ohhhh...I think that would work." He asked what I was talking about and I told him I was working on a math problem.  Not impressed. We didn't talk about it any more. When we arrived home, I put my ideas on paper and created the video to send to Jenny explaining my thinking.


As I spent my weekend working on math problems, my wonderful husband David simply shakes his head. He is an artist and musician at heart and often doesn't see the beauty of math as I do. He tolerates my endless talking about an "I love math generation" and at least acts interested when I get going on math problems. He is a self-proclaimed math hater. In all honesty, that makes me very sad.

So I posed this problem to David. 600 ÷ 48. (He had not seen what I had been working on.) I asked him to share how he would attack that problem. You know what he said.....
"I'd take 600 ÷ 50 and get 12. But I know that is 2 too many in each group so I have to do something with the 2's."

HE IS BRILLIANT MATHEMATICALLY! Why didn't I just ask him (the self proclaimed math hater) to explain the darn thing to me! Well Mr. Smarty Pants, what about those 2's?

Below is the visual model of what happens in that problem and a quick visual explanation of the other 2 methods as well.

My point is this. In order to become an "I love math generation" we need to foster creativity in thinking instead of forcing memorization and algorithms. I think many people out there who hate math only hate math because of their school experience. After this experience with David, I think that is why he hates math. 

We can change that. We MUST change that!

I love you David!

NOTE: The video is "raw". If I was producing these professionally I would clean up some of my errors in how I say things mathematically. Perhaps I will do that someday. In the end you see I say "divide by a half" when actually I meant "divide by 2". Because I know Jenny knew what I meant, I didn't fix it. You'll get the point.