In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on April 10, 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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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 00:19

Okay, so this Wednesday, our math problem was 34 times 46. How would you solve this problem? Pause the podcast. Solve it any way you want. The problem is 34 times 46.

Pam 00:33

Bam. Alright, I'm going to go first.

Kim 00:35

Okie doke.

Pam 00:36

Because. And this problem...

Kim 00:38

Because. Because I want to.

Pam 00:41

Because I want to. Pretty much. This problem, my first instinct when I look at 34 times 46, is "Yuck."

Kim 00:48

Yeah.

Pam 00:48

So, none of the usual culprits are jumping out to me, except I'm noticing that they are both 6. Both numbers, 34 and 46, are 6 away from 40. So, I'm thinking about writing this as 40 minus 6 for 34 times the quantity 40 plus 6 for 46. So, 40 times 40 is 1,600. The insides add out, and then I've got negative 36. So, 1600 minus 36. Play a little I Have, You Need is 15. I got to think. 64.

Kim 01:24

Mmhm. Mmhm.

Pam 01:25

Yeah, 64. 36,64. Yep, yep. Alright. What are thinking about?

Kim 01:30

What did you just say?

Pam 01:32

1,564.

Kim 01:33

Oh, I thought you said 3,664. You were talking about the partner. I was like, "Mmm..." Okay, I'm with you now.

Pam 01:40

Read my mind. Don't. Don't. It's a scary place in there.

Kim 01:45

Oh, gosh. Okay, I'm going to be honest with you. We could talk about some partial products. I mean, I could say like 34 times 50 and do a little bit Over. But sometimes there's a problem where it just screams, like that is so overwhelmingly good. It's like when we talk about the plus 99. Like, plus 99 is plus 100 minus 1. We wouldn't really. I mean, kids could do whatever they want, right? But we would so heavily nudge the Over strategy for plus 99. And I think this is a prime example of a problem that really heavily we would nudge difference of squares. Now, if that's not, you know, where you're at age wise, then okay. But anything less than that at this point for me is like ho hum. Do I have to have one? No. I don't... I mean... There are things you could do. But.

Pam 02:48

Well, let me tell you what I started.

Kim 02:49

Let's highlight how great it is.

Pam 02:51

It's so good.

Kim 02:52

Yeah.

Pam 02:52

I started playing because I just like if I didn't have the difference of perfect squares, what could I do? Or the difference of squares. I shouldn't have said perfect. The difference of squares. I could have thought about 34s.

Kim 03:06

Yeah.

Pam 03:06

And I could find two 34s, double that to get four 34s. Add those together to get six 34s.

Kim 03:13

Yeah.

Pam 03:14

Scale up the 4 times 40. And I'm almost there. That would be 1,360. And then, I could add the 40 and the 6 together.

Kim 03:22

Yeah.

Pam 03:23

I could do that. And that's maybe what I would. You know, if I wasn't already. Because, you know, we might have kids that are fourth, fifth grade that they haven't really care about.

Kim 03:30

Sure, sure, sure.

Pam 03:31

Yeah. Yeah. Cool.

Kim 03:33

Alright

Pam 03:33

Alright. We can't wait to see what you do each week. Join us on MathStratChat, and let us know how you think about the problem. And comment on each other strategies.

Kim 03:42

Yeah, we post the problems on Wednesdays at 7pm Central. So, when you answer tag Pam and use the hashtag MathStratChat. Then, join us to hear what we're thinking about the problem. We love having you a part of the Math is Figure-Out-Able movement!