# Math is Figure-Out-Able!

Math teacher educator Pam Harris and her cohost Kim Montague answer the question: If not algorithms, then what? Join them for ~15-30 minutes every Tuesday as they cast their vision for mathematics education and give actionable items to help teachers teach math that is Figure-Out-Able. See www.MathisFigureOutAble.com for more great resources!

## Math is Figure-Out-Able!

# #MathStratChat - October 30, 2024

In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on October 30, 2024.

Note: It’s more fun if you try to solve the problem, share it on social media, comment on others strategies, before you listen to Pam and Kim’s strategies.

Check out #MathStratChat on your favorite social media site and join in the conversation.

Twitter: @PWHarris

Instagram: Pam Harris_math

Facebook: Pam Harris, author, mathematics education

**Pam **00:01

Hey, fellow mathers! Welcome to the podcast where Math is Figure-Out-Able. I'm Pam Harris.

**Kim **00:07

And I'm Kim Montague.

**Pam **00:08

And this is a MathStratChat episode because we chat about our math strategies. Every Wednesday evening, I throw out a math problem on social media, and people from around the world chat about the strategies they use and comment on each other's thinking. Hey, Kim.

**Kim **00:23

Hey. So, this Wednesday, our math problem was 90% of 10. And we want to know how you would solve this problem. Pause the podcast. Solve it however you'd like. The problem is 90% of 10.

**Pam **00:36

You were probably totally thinking about your strategy, and you're like, "Oh, my turn to talk!" Right? Because you were like (unclear).

**Kim **00:41

Maybe.

**Pam **00:41

You're were trying to... Yeah. You were like, "I'm going to get the jump." I'm going to get the jump. I'm going to get the jump on Pam, and make sure that you have the cool strategy.

**Kim **00:49

I will let you go first.

**Pam **00:51

Okay, so I actually chose this problem because I wanted to play around with the the fact that there was kind of the same numbers happening.

**Kim **01:00

Mmhm.

**Pam **01:00

In fact, I've chosen the last couple problems that way that there's kind of this like... Yeah. Because like 90% of 10, there's this implicit 10% hanging around.

**Kim **01:10

Mmhm.

**Pam **01:10

So, like there's this 10% and 10. Blah, blah, blah.

**Kim **01:14

Mmhm.

**Pam **01:14

So, I'm actually going to find 10% of 10. And 10% of 10, if I divide 100% by 10 to get 10%, then I'm going to divide 10 by 10 to get 10%. So, that's 1. So, 10% of 10 is 1. Right? So, if 10% of 10 is 1, then 90% of 10 is going to be one less than 10, which is 9. That may have been way too convoluted, but that is what I was thinking about today.

**Kim **01:43

You want to know how creepy our brains are sometimes?

**Pam **01:45

Oh, no.

**Kim **01:46

You know what I wrote on my paper?

**Pam **01:47

What?

**Kim **01:48

I wrote 9 times 10% times 1 times 10. And I was like...

**Pam **01:58

Okay, okay.

**Kim **01:59

And I drew a line to connect the 10% of 10.

**Pam **02:03

Mmhm.

**Kim **02:05

And I said, "Okay, that's just 1, so 9 times 1 times 1 is 9." And it feels similar to what you...

**Pam **02:11

Yeah. That's interesting.

**Kim **02:13

Yeah, the pulling out the 10% and the 10

**Pam **02:16

Yeah. Okay, so let me just for fun. If we're thinking about 90% of 10, we could use the commutative property to think about 10% of 90. And 10% of 90 is just 90 divided by 10. And 90 divided by 10 is also 9. So, a couple different ways of thinking about that problem.

**Kim **02:32

Yeah.

**Pam **02:33

Yeah.

**Kim **02:33

Alright, we love scrolling through the feeds and finding out what you do each week, so we hope you join us on MathStratChat and let us know how you think about the problems. And while you're there, comment on everybody else's strategy.

**Pam **02:45

We post the problems on Wednesday around 7:00 pm Central. When you tag... No, when you answer. When you answer, tag me and use the hashtag MathStratChat. Or tag, answer. Whatever. Then join us here to hear how we're thinking about the problem. We love having you as part of the Math is Figure-Out-Able movement because Math is Figure-Out-Able!