In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on May 10, 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.
Hey, fellow mathematicians! Welcome to the podcast where Math is Figure-Out-Able! I'm Pam.
Kim:
And I'm Kim.
Pam:
And this episode is a MathStratChat episode where we chat about math strategies. Every Wednesday evening, I throw out a math problem on Twitter, Facebook, Instagram, all the places, and people from around the world chat about the strategies they use. It is super to see everyone's thinking.
Kim:
So, this Wednesday, our math problem was 24 times 36. We'd love to know how you would solve this problem. Pause the podcast and solve it any way you want. The problem is 24 times 36. Solve it, and then come back to hear how we solve it.
Pam:
Alright, Kim, I'm going to ask you to go first today. I want to hear how you are thinking about 24 times 36.
Kim:
Okay. So, the first thing I thought about was 24 is really close to 25. And, you know I do like the quarters, the coins, the... I do (unclear).
Pam:
I will never forget the day. We were filming. I wasn't there for filming, but I watched it after. This is early, right? And you were doing a thing for the state of Texas. And you said to this kid, "Sure. Wish I knew something about quarters." I'll never forget that. Because you(unclear) like, "Do you know something about quarters?" And I was like, "I don't know anything about quarters. How are you thinking about quarters?" Alright, keep going.
Kim:
That's amazing. So, 25 times 36, I know is$9.00. And how do I know that? I mean, I just see the 4 and the 9 in the 36. 4 times 9. And so, I just know it's $9.00.
Pam:
Because 4 quarters is like 100 cents. Times that 9. Okay.
Kim:
Yeah, yeah.
Pam:
Yep, thanks. Okay.
Kim:
So, then if 25 times 36 is 900, then twenty-four 36's would just be one less 36, which means that it would be 864.
Pam:
And how did you do the 900 minus 36?
Kim:
I literally thought, "If I have 36, what do I need to make 100."
Pam:
Mmhmm.
Kim:
And I just know that combination of 36 and 64.
Pam:
Bam! Super cool. Great. Alright, I have been playing around with something kind of that we learned a little bit later in algebra. I'm trying to get better at how I could represent it with an area model. But for now, I'm just going to talk about that I could think about 24 times 36 as the quantity 30 minus 6 because 24 is like 30 subtract 6. Times 30 plus 6. So, all you algebra teachers out there, smile just a little bit because if I can think about 30 minus 6, that quantity times the quantity 30 plus 6, then I can multiply the 30 times 30 to get 900. The minus 6 times 30, and the plus 6 times 30 add to 0. The minus 6 times plus 6 is minus 36. And I end up in the same place you were, Kim, which is 900 minus 36. And I would also think about I Have, You need to get the partner, to get 864. Nice. Yeah, super cool.
Kim:
I wish that I... I'm not going to say, "I wish". I'm going to seek out that strategy more often because it doesn't occur naturally to me. So, I mean, I could wish it, and it's not going to happen. But I'm going to put some work into looking for that strategy more often.
Pam:
Well, and can I tell you the work that I'm putting into it? Yeah, I'm writing MathStratChat problems for which it works.
Kim:
Cool. I'll be on the lookout.
Pam:
Yeah. And honestly, that's often what I do. If I find something, I hear mathy people doing something, and I'm like,"Oh, I want my brain to do that," then, I write a Problem String to help my brain wrap itself around those relationships, so that then I own it better. Yeah, it's a cool way.
Kim:
Very cool.
Pam:
Cool.
Kim:
Alright, listeners. We can't wait to hear your math strategy. I wonder if it was like one of ours or something entirely different. Go ahead and represent your thinking. We'd love to see a picture of your work. And tell the world on social media. While you're there, check out what other people did and comment on their thinking as well.
Pam:
Yeah, and tag me on Twitter at @PWHarris. Instagram, Pam Harris_math. And on Facebook, Math is Figure-Out-Able. And use the hashtag MathStratChat. And make sure you check out the MathStratChat problem that we post every Wednesday around 7:00 pm Central time, and then pop 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. Let's keep spreading the word that Math is Figure-Out-Able!