Friday, 17 May 2013

Fawn vs. Nathan

I had my grade 9 class work on this problem today:

A colleague gave me a version of this that was fully scaffolded, but I thought it would be much richer if it was more open.  And I threw a couple of tweep's names in there for fun.

They worked in groups and wrote solutions on their whiteboards.  Here was the first attempt:

Although Fawn probably likes this, I asked if volume should determine the price.  A. said "Surface area!" and this is what he produced:

And another solution:

Along the way I heard a lot of "Fawn's right!" and some "Nathan's wrong!" (maybe I should have won your little exponent game, Nathan)

They worked out that the volume of the large fish tank was 8 times the volume of the small one.  The surface area of the large one was 4 times the surface area of the small one.  The price of the large one was 4.6 times the price of the small one.  Here is a nice summary (she originally forgot that there was no top so had to subtract after):

Bottom line here - Fawn is right! (always, otherwise she punches you)


  1. This is the BEST post ever, Mary. I love you. I'm always right. Somebody else is always wrong. End of story. :)

  2. Mary. This is the WORST post ever written. You should be ashamed.

  3. Seems like someone is a little sensitive. If it makes you feel any better did think you were right to question the price. But really, why would you question Fawn?

    1. "But really, why would you question Fawn?" Amen. (You got the wrong memo though, I don't punch people, just hug them A LOT.)