Math is Figure-Out-Able with Pam Harris

#MathStratChat - November 15, 2023

November 15, 2023 Pam Harris
Math is Figure-Out-Able with Pam Harris
#MathStratChat - November 15, 2023
Show Notes Transcript

In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on November 15, 2023. 

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

Want more? Check out the archive of all of our #MathStratChat posts!

Pam  00:00

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


Kim  00:07

(laughs) And I'm Kim. 


Pam  00:08

What are you laughing about?


Kim  00:09

(laughs) I don't know.


Pam  00:09

And this episode is a funny MathStratChat episode, where we're not sure why we're laughing, but we chat about math strategies. Every Wednesday evening, I throw out a math problem on social media and people from around the world... Hey, we're getting India lately, which is super cool. Thanks for the India strategies! Where they chat about the strategies they use and comment on other's thinking.


Kim  00:30

Okay, so this week, we had this problem 149 plus 155. We're wondering how you want to solve the problem. Pause the podcast. Solve it before you hear what we're going to do.


Pam  00:44

Whether we do something well or not. Okay, so I'm going to go first because I want to. Hey, so I'm noticing that the last few weeks, we've been doing some problems where doubles are popping out. 


Kim  00:54



Pam  00:54

So, a couple of weeks ago, we did 250s. So, if you know 250 and 250 was 500, it was helpful. Last week we did 350s. And so, if you know 350 and 350 was 700, that was helpful. Today, 149 and 155 is screaming 150. 


Kim  01:11



Pam  01:12

So, if I know the double of 150 is 300, then I think I can think about 149 being 1 less than 150 and 155 being 6 more than 150.


Kim  01:25

Wait, I'm listening. I'm listening. You said 155 is 6 more.


Pam  01:29

So, 1 less and 5 more. Wait, did I say something wrong? Is that what you're saying?


Kim  01:33

You said 155 is 6 more than 150.


Pam  01:35

Oh, I was thinking about that 1. That extra 1 from the 149. Okay, let me try that again. 149 is 1 less than 150. 155 is 5 more than 150. So, 1 less and 5 more is just 4 more. Those kinds of add out. So, just 4 more. So, 4 more than the double of 150 of 300. 4 more than that is 304. 304. 


Kim  01:57

Yep. Cool. 


Pam  02:00

It takes a whole lot longer to say than I actually did.


Kim  02:02

It does. Yeah. 


Pam  02:03



Kim  02:03

It does, right?


Pam  02:04

It's like, on my paper, I literally wrote plus 1 under the 149, and then 150. And minus 5 under the 155, and wrote 150. 


Kim  02:15



Pam  02:15

Right? And then, I just had the 300.


Kim  02:17



Pam  02:19

And then, adjust from there. Yeah. And the plus 1 and the minus 5 was the four. And we just adjust the 4. 


Kim  02:23



Pam  02:23

So, yeah, it takes a whole lot longer to talk about. Anyway. 


Kim  02:25



Pam  02:25

What did you do Kim?


Kim  02:26

Which, I think sometimes makes people think that kids are slower. But taking a moment to describe your thinking is quite a bit slower. So, I...


Pam  02:40

Wait. So, you mean people might hear a kid explain their thinking, and go, "Ugh. Don't do that. That's so laborious. It took so long. Just do the algorithm." When in reality, it just took them long to describe not actually to do.


Kim  02:52



Pam  02:53

Agreed. Yeah. Okay.


Kim  02:54

So, I wrote on my paper 155 plus 150. And then, I also use that double that you're talking about. So, when I thought about 155 and 150, I kind of saw the 150 and 150 within that.


Pam  03:10



Kim  03:11

So, I thought about 300, but it's 5 more is 305. And then, because I had added 1 too much to make it 150 instead of 149, then I backed up 1 and got the same 304.


Pam  03:23

Nice, I like it. Nice Over. So, we both used... I kind of did a more of a Give and Take. You did more of an Over. But we both used that double of 150. Super cool.


Kim  03:35

I'm pausing. You just said it was a Give and Take, and I want to think about that for a second before I... Is that Give and Take? I don't. Say more about that.


Pam  03:47

Maybe mine wasn't exactly a Give and Take. It kind of felt like I was adjusting. 


Kim  03:52

It's kind of... Yeah. Definitely finding the double within.


Pam  03:57

Would Give and Take have been more of a plus 1 to 149 to be 150, minus 1 from 155 to be 154, and then thinking about 150 and 154 as 304? That would be more of a Give and Take. 


Kim  04:13

Yeah, yeah, yeah. Like, (unclear) the Give and Take, and then also noticing. 


Pam  04:18

And then, noticing the double.


Kim  04:19

That's maybe where your Give and Take can be more simultaneous, but then also kind of sequential. Like, you know how you still want that to be a little more sequential?


Pam  04:30

Well, because I was less sophisticated, but yeah. 


Kim  04:33

Oh. Well, I wasn't going to say that. Okay, anyway.


Pam  04:38

It's okay. I can own it. I can own it. 


Kim  04:39



Pam  04:40

Yeah. Oh, in fact, we have a podcast episode coming up where we're going to talk about that. Yeah. Anyway, sorry. Hey, spoiler alert! Really cool podcast episode coming up.


Kim  04:50

Alright. We're moving on. We can't wait to see your thinking. We always love checking out that on MathStratChat and every other social media, so take a picture after you've solved problem and let us know what you're thinking. Don't forget to comment on other's work.


Pam  05:04

Yeah, and tag me, so I can reply, and smile, and like, and all the things. And use the hashtag MathStratChat. And make sure you check out the MathStratChat problem that we'll post every Wednesday around 7pm Central Time, and then come back here to hear how we're thinking about the problem. We love having you as part of the Math is Figure-Out-Able movement. Thanks for spreading the word that Math is Figure-Out-Able!