## Lists, Infinite Sums…

I’m not sure where I was going with this post.  I had an idea at school, and I wrote “blog about infinite sums and lists” on a post-it, and stuck it to my laptop.  So here I am, not really sure where to go with it.

Oh!  The same kid who is reading Uncle Petros figured out infinite sums today, sort of.  I asked a question in the academic prep class.  On a side note, I find they are a very captive audience.  Doing my little problems gets them out of doing “formal” work, but they are still learning…teacher: 1, students: 0.  Anyway, I said “What’s 1/2 plus 1/4 plus 1/8…and keep multiplying the bottom by 2 and go on forever.”  Someone said “a whole.”  I said yep.  They laughed because it was a complete guess, but I saw people write it down.  I asked “What’s 1/3 + 1/9 + 1/27…and keep multiplying the bottom by 3, and go on forever.”  1/2.  I figured this wasn’t a complete guess.  I went on with 1/4, 1/5…same kid kept answering.  I asked him if he knew.  He said, and I am thrilled with this quote…”no, but there are a lot of patterns in math.  I figured this was one of them, too.”

So I sort of lied, he didn’t really “figure out” the sum per se, but he did see the pattern.  And that’s half the battle.  Heck, this was a 9th grader in algebra 1.  Seeing that pattern should be a whole battle.  Kudos, Matt.

That takes care of the “infinite sums” part of my post-it.  As for the “lists,” I’m not really sure.  I’ll get back to you.  Have a super evening.