In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on July 19, 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.
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Facebook: Pam Harris, author, mathematics education
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Hey, fellow mathematicians! Welcome to the podcast where Math is Figure-Out-Able. I'm Pam.
And I'm Kim.
And this episode is a MathStratChat episode. MathStratChat is where every Wednesday evening, I throw out a math problem on Twitter, Facebook, Instagram, all the social media and people from around the world chat about the strategies they use. We love seeing everyone's thinking,
We sure do. So, this Wednesday, our problem was 3,618 minus 2,412. And we're wondering how would you solve this problem? Pause the podcast, solve it however you'd like. The problem was 3,618 minus 2,412. Solve it, and then let's listen to how we solve it.
Okay, Kim, Kim, Kim. Kim!
I want to do your thing.
So, I've been having fun trying to see problems the way that you saw one a couple episodes ago.
Alright. So, I'm looking at 3,618 and 2,412. And I'm seeing 36 hundred and 24 hundred, and those feel like 12s to me, so I can just almost see two 12s and three 12s, means I'm left over with one 12 hundred. So I literally wrote down 12 underneath. So, I actually line these up vertically. Which some people might like, "Pam! How dare you line them up vertically!" Ya'll, it's not about how they look. Vertical, horizontal. It's about what you then do with the relationships. And so, what I'm going to do with relationships is think about that. 36 hundred minus the 24 hundred is 12 hundred. Then, I just got 18 minus 12 leftover because the numbers were 3,618 and 2,412. So, the 18 tacked on and the 12 tacked down. 18 minus 12 is 6. So, my final answer is 1,206. 1,206.
So, I know we've been talking about kind of thinking about how many hundreds in the number. But for this one in particular, I was actually thinking about the number of tens in the number. So...
Wait, wait, wait. What?
So, 3,618 has 361 tens.
Ha! Sure enough.
And then, 241 tens in the other one. So, I thought about kind of if I was thinking about tens, I was thinking about 361 minus 241, the number of tens, and I got 120 tens, which is 1,200. And then, I did the last 8 minus 2, which is 6. So, I got...
And 1,200 and 6 is 1,206. Sorry, yeah. I just got excited, so I finished your.
It's all good.
Sorry, my bad, my bad.
Yeah. So, you were thinking about 100s in the number, and I was thinking about 10s the number.
Sure enough. Huh. So, I'm also aware that now that I'm looking kind of back at the work I just wrote down for you, that we also could have thought of these as 3,000 minus 2,000 is 1,000. 600 minus 400 is 200. 10 minus 10 is 0 and 8 minus 2 is 6. And I would have thought about 1,206. Again, going greatest to smallest, right? It's only the algorithm that kind of forces us to go smallest to biggest, right to left. Now, that we're all kind of thinking about numbers, and relationships, and magnitude, I almost always look at the big numbers first. Cool, nice problem.
Yeah. Yeah. (unclear).
Alright, I like it.
So, we can't wait to see what your strategy is. I wonder if it was like one of ours. Represent your thinking, take a picture of your work or screenshot on your phone, and tell the world on social media. Help us spread the word. And while you're there, check out what other people did and comment on their thinking.
Yeah, and tag me on Twitter at @PWHarris. Or Instagram, PamHarris_math. Facebook, Pam Harris, author, mathematics education. And use the hashtag MathStratChat. And then, check out the next MathStratChat problem that we'll post Wednesday somewhere around 7pm Central Time, and then pop back here to hear how we're thinking about the problem. Ya'll, thanks for joining us as part of the Math is Figure-Out-Able movement. And keep spreading the word that Math is Figure-Out-Able!