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 - March 27, 2024
In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on March 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
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Facebook: Pam Harris, author, mathematics education
Want more? Check out the archive of all of our #MathStratChat posts!
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 00:07
And this episode is a MathStratChat episode, where 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.
Kim 00:22
I have to totally admit, I am clicking around on my computer, right this very moment.
Pam 00:27
I was like, "Hey, Kim. Your turn."
Kim 00:29
Well, I moved some stuff on my screen, and I literally cannot find.
Pam 00:35
Can't find where we are.
Kim 00:36
No, I mean.
Pam 00:38
Okay, keep looking. Okay, this Wednesday, our math problem was 16 times 24. How would you solve this problem? Pause the podcast, solve the problem any way you want. The problem is 16 times 24. Go. Alright, so you don't need to find your stuff now. You can just (unclear).
Kim 00:52
Okay, well, but now I need to think about the problem. Tell me the problem again. (unclear).
Pam 00:56
16 times 24. I'm going to go while you're thinking.
Kim 01:03
Okay.
Pam 01:04
Okay, I'm going to think about 25 times 16.
Kim 01:08
Ah! Okay.
Pam 01:09
Is that what you wanted?
Kim 01:09
Yeah. No, that's what I was thinking. But go ahead. I'll come up something else.
Pam 01:12
Okay. Well, I was going to think about 25 times 16.
Kim 01:15
Yep.
Pam 01:15
Because then I could just get one less 16, then I would have 24 times 16. So, 25 times 16. I can think about as one-fourth of 16. Like, 0.25 times 16. And then, I have to scale it back up. So, it's not 0.25 times 16. It's 25, so that's times 100. So, it would be 400. So, 25 times 16 is 400. So, 24 times 16 would be 16 less. Play a little I Have, You Need. That's 384.
Kim 01:46
Yeah.
Pam 01:46
Okay, so.
Kim 01:47
(unclear).
Pam 01:47
Sorry, I took yours. What were you thinking?
Kim 01:49
No, that's okay. I...
Pam 01:51
I bet you were probably doing like Doubling and Halving or something (unclear).
Kim 01:55
Well, the first thing I thought about was the 25s. But I don't know why. But I wrote the problem down, and I... Maybe it's because 24, but I feel like there's a lot of 4s. And I don't know. Yeah, Double Halving would have been nice because the 16. You just keep doing it. But I actually wrote down 4 times 4 times 6 times 4.
Pam 02:17
Oh.
Kim 02:18
And I at first was like, "Do I know 4^2?" And I do. That's 64?
Pam 02:26
You mean 4^3.
Kim 02:27
Yeah, that's what I mean.
Pam 02:28
Yeah. Okay.
Kim 02:29
I am a mess today! We're busy ya'll. We're busy. So, yes, 4^3 is 64. So, that would be 64 times 6, which, you know, is fine. But so then I thought... I feel like I'm just playing at this point. So, then I thought about 64 times 5.
Pam 02:49
Oh, my gosh. That's where I just went.
Kim 02:51
Yeah, so 64 times 10 would be 640, so times 5 means it's 320. And then, I have one more 64. So, then I just wrote down 320 plus 64 is the same 384.
Pam 03:04
Nice flexible factoring.
Kim 03:06
And here's the thing. So, because you and I are not like, "What's the answer? What's the answer? What's the answer?" We're okay with the space to say, "What else would I want to do?"
Pam 03:17
Totally.
Kim 03:18
It's playing, and messing around, and thinking about all the relationships that we need? Yeah.
Pam 03:26
So, when you had the 4 times 4 times 4 times 6, I started to wonder how many2s that would be.
Kim 03:33
Mmm.
Pam 03:35
Which also played into sort of the Doubling and Halving that I was thinking about as well.
Kim 03:39
Mmhm.
Pam 03:39
So, like it would be 2, 4, 6, and one more 2. So, like it's 2^7. So, if I know 2^7, that will be 2^7 times 3. That would be a way of thinking about it. But I'd also doubled and halved while you were talking, and I ended up with 192 times 2, which is also 384. Yeah. When you said doubling and halve because the 16 is nice, you were recognizing 16 as a bunch of 2s. Right, power of 2. So, you knew you could halve it all the way down.
Kim 04:06
Yeah.
Pam 04:06
Yeah, that's really cool. Alright, nice.
Kim 04:08
Awesome. We can't wait to see what you do. Every single week, we get excited to check it out. So, join us on MathStratChat (unclear).
Pam 04:14
Oh, I just thought of another one.
Kim 04:15
NO!
Pam 04:16
Okay, nevermind.
Kim 04:17
Let people do something. And let us know how you think about the problems. And it's super cool when you comment on other people's strategies.
Pam 04:24
Yeah, and you might try something. There's something else lurking in that one that I can't believe I didn't think about. Alright, so we'll post problems... Oh, my goodness. We post problems on Wednesdays at 7pm Central time. When you answer, tag me and use the hashtag MathStratChat. 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!