Math is Figure-Out-Able!

#MathStratChat - November 27, 2024

Pam Harris, Kim Montague

In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on November 27, 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  00:00

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

 

Kim  00:06

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 strategies they use. And we love it when you comment on each other's thinking.

 

Kim  00:21

Okay. So, this week, our math problem was compare four-ninths and five-elevenths. How would you solve this problem? Pause the podcast. Solve however you'd like the problem is four-ninths and five-elevenths. Give those a compare. 

 

Pam  00:34

Alright, so Kim, I am aware that I have the same paper out that I had for last week's MathStratChat, which was four-ninths compared to six-elevenths.

 

Kim  00:43

Mmhm.

 

Pam  00:44

And we reasoned a couple ways to find that four-ninths is less than six-elevenths.

 

Kim  00:49

Mmhm. 

 

Pam  00:50

But now, we've got one less eleventh. So, four-ninths is less than half because four and a half-ninths is a half. Five-elevenths is less than half because five and a half-elevenths... So, what I just wrote down was four and a half-ninths and five and a half-elevenths. So, four -ninths is just a half of a ninth under a half. And five-elevenths is a half of an eleventh under one half. Since an eleventh is smaller than a ninth, five-elevenths is not as far from a half as four-ninths. Right? Oh, I love that I could just do that. 

 

Kim  01:39

Love that. 

 

Pam  01:40

Notice. So, wait. I have to say that again. 

 

Kim  01:42

Say it again. Yeah, yeah.

 

Pam  01:43

So, five-elevenths is not as far under a half as four-ninths. Yeah. (unclear).

 

Kim  01:51

And so you think it's bigger. 

 

Pam  01:52

So, I think five-elevenths is still bigger. Not as far under. Yeah. Right?

 

Kim  01:57

Wait, say that again. You think what's bigger? 

 

Pam  02:01

Yeah, good question. 

 

Kim  02:03

Are you... Can you draw? Are you drawing something? 

 

Pam  02:05

Um, no. 

 

Kim  02:07

Oh, maybe put it on a number line. 

 

Pam  02:08

Well, I have five and a half-elevenths. So, let me just compare that again. five-elevenths to five and a half -elevenths. I'm a half of an eleventh under one-half. And a half of an eleventh is smaller... Yeah. 

 

Kim  02:24

Yeah.

 

Pam  02:24

Yeah, so it's closer. So, it is. It's bigger. Five-elevenths is bigger than four-ninths.

 

Kim  02:28

I love that when you said that to yourself a second time, you drastically different. You're like, "Yeah, it is." 

 

Pam  02:34

Yeah. 

 

Kim  02:34

Convinced. Confident. 

 

Pam  02:35

Nice.

 

Kim  02:36

Nicely done. 

 

Pam  02:37

Okay, I have no idea what you're going to do.

 

Kim  02:40

I actually started to...

 

Pam  02:43

Thanks for letting me have my way first. 

 

Kim  02:44

No, it's okay. Well, I started to go down the path that you were, and then I realized that you were doing that, so I decided to do something different. And really, elevenths and ninths are not my favorite. But for whatever reason, I think that I would just scale up for this one, and I'd say... Would I? I guess I would. (unclear). 

 

Pam  03:04

Do you want more time? 

 

Kim  03:05

No, because I do think there's a world where it's okay to scale up sometimes.

 

Pam  03:11

Sure.

 

Kim  03:11

(unclear).

 

Pam  03:12

Yep, yep. 

 

Kim  03:15

So, I'm going to call five-elevenths the same as equivalent to 45/99. And I'm going to call four-ninths equivalent to 44/99.

 

Pam  03:26

Oh, those are so close, eh? 

 

Kim  03:28

Yeah. yeah. So, it's 1/99. No wonder it's challenging to tell without a little bit more thinking. They're so close. 

 

Pam  03:38

Yeah.

 

Kim  03:38

So, five-elevenths.

 

Pam  03:39

Cool problem.

 

Kim  03:40

Yeah, yeah.

 

Pam  03:41

You're cool, Kim. You're so cool. Alright, y'all. 

 

Kim  03:43

You wrote it!

 

Pam  03:44

We can't wait to see... Yeah, I just... Yeah, but I knew they were close. I don't know if I knew how close.

 

Kim  03:48

Yeah. 

 

Pam  03:49

We can't wait to see what you do each week. Join us on MathStratChat and let us know how you are thinking about the problems. And while you're there, comment on each other's strategies. 

 

Kim  03:57

Yeah, Pam posts the problem on Wednesday evenings at 7:00 pm Central, and when you answer, you can tag her and use the hashtag MathStratChat. Then join us here to hear what we're thinking about the problem.

 

Pam  04:07

We love having you as part of the Math is Figure-Out-Able movement, because Math is

 

Pam and Kim  04:13

Figure-Out-Able!