Friday, April 15, 2011

Math Teachers at Play #37

This edition starts with a puzzle (thank you, Caroline!): Use five 5's to make 37. I don't see a way yet. Do you?

I just had a lovely time following up the links. One of my favorites was...



  1. (((5+5)/5)+5)*5....


  2. So this is along the line of the four 4's problem (use four 4's to count to 20 or 100), How can we use problems like this with students? I mean beyond, just asking them to come up with the answers or make a calendar using four 4's for each day. What questions can we ask the kids, how can we get them to reflect and think about things like "A number is all the ways you can name it"?

  3. Mr. Steve, I think that's an interesting question. I don't have a good answer, though.

    Before I allowed retesting, I offered extra credit. The four 4's puzzle was a great opportunity to get my beginning algebra students thinking about basic arithmetic more deeply.

    I think the value is in creating engaging puzzles that will draw them into working harder at math, because they just want to.

  4. Try these too:

    Are You a Math Genius

  5. Sue,

    This post inspired me to write some Python code and a blog post of my own.

    You can find it here:

    I hope you enjoy it!


  6. Cool. I'm glad this problem inspired you to write a program. I've been slowly learned Geogebra that way. I want to do something, and I painfully work my way through the less obvious 'features', trying to put it together.


Math Blog Directory