In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on February 12, 2025.
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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Pam 00:00
Hey, fellow mathers! Welcome to the podcast where Math is Figure-Out-Able. I'm Pam Harris.
Kim 00:07
And I'm Kim Montague.
Pam 00:08
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 00:24
Okay, so this Wednesday, our math problem was 9 times 25. How would you solve this problem? Pause. Solve it however you'd like. The problem is 9 times 25
Pam 00:35
Alright, so, Kim, I thought I'd do a problem that was relatively doable.
Kim 00:40
Okay.
Pam 00:40
Maybe because I hope that it builds in the problem next week, so maybe everybody can be paying attention to maybe strategies you see this week that you hadn't thought of that might lead, maybe lead into something hadn't thought of next week. I don't know. Maybe not. But go ahead. What do you... I sure wish I knew something about quarters.
Kim 00:58
Well, I'm going to say that I know eight quarters is $2.00.
Pam 01:02
Okay.
Kim 01:02
So, nine quarters is 225.
Pam 01:04
Nice. And you know eight quarters is $2.00 because you've dealt with quarters a lot. But I might back that up to say four quarters in $1.00.
Kim 01:12
Mmhm.
Pam 01:13
So, double that, and then 1 more. Cool. I'm going to think about Doubling and Halving.
Kim 01:19
Okay.
Pam 01:20
So, 9 times 25, I can think about halving nine to 4.5 and doubling 25 to 50. And I'm gonna do it one more time. Half of 4.5 is 2.25, and then double 50 is 100. And 100 times 2.25 is 225.
Kim 01:38
I love that you chose that strategy because I think so many times people avoid using double halve when there's some odd numbers.
Pam 01:47
Odd number, mmhm.
Kim 01:47
But you can halve an odd number. (unclear).
Pam 01:51
Yeah. Hey, Kim, would you... If I just asked you, pretty please, would you also over that one?
Kim 01:59
Yeah, I would think about ten 25s, which is 250. And then back up one 25 to get to 225.
Pam 02:07
Bam. So, three fine strategies for 9 times. 25. Cool.
Kim 02:11
Fantastic. Okay, well, we can't wait every week to see what you guys do. Join us on MathStratChat, and let us know how you think about the problems. And please be sure to comment on each other's strategies.
Pam 02:21
We love it when you do that! Ya'll, we post the problems on Wednesdays around 7:00 pm Central time. When you answer, tag me and use the hashtag MathStratChat. Then join us to hear how we're thinking about the problem. We love having you as part of the Math is Figure-Out-Able movement because Math is Figure-Out-Able
