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.
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Hey, fellow mathematicians! Welcome to the podcast where Math is Figure-Out-Able! I'm Pam.
(laughs) And I'm Kim.
What are you laughing about?
(laughs) I don't know.
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.
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.
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.
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.
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.
Wait, I'm listening. I'm listening. You said 155 is 6 more.
So, 1 less and 5 more. Wait, did I say something wrong? Is that what you're saying?
You said 155 is 6 more than 150.
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.
It takes a whole lot longer to say than I actually did.
It does. Yeah.
It does, right?
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.
Right? And then, I just had the 300.
And then, adjust from there. Yeah. And the plus 1 and the minus 5 was the four. And we just adjust the 4.
So, yeah, it takes a whole lot longer to talk about. Anyway.
What did you do Kim?
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...
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.
Agreed. Yeah. Okay.
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.
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.
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.
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.
Maybe mine wasn't exactly a Give and Take. It kind of felt like I was adjusting.
It's kind of... Yeah. Definitely finding the double within.
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.
Yeah, yeah, yeah. Like, (unclear) the Give and Take, and then also noticing.
And then, noticing the double.
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?
Well, because I was less sophisticated, but yeah.
Oh. Well, I wasn't going to say that. Okay, anyway.
It's okay. I can own it. I can own it.
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.
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.
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!