Pam  00:01

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 is a MathStratChat episode because 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. Hey, Kim. 

Kim  00:23

Hey. So, this Wednesday, our math problem was 90% of 10. And we want to know how you would solve this problem. Pause the podcast. Solve it however you'd like. The problem is 90% of 10.

Pam  00:36

You were probably totally thinking about your strategy, and you're like, "Oh, my turn to talk!" Right? Because you were like (unclear). 

Kim  00:41

Maybe.

Pam  00:41

You're were trying to... Yeah. You were like, "I'm going to get the jump." I'm going to get the jump. I'm going to get the jump on Pam, and make sure that you have the cool strategy. 

Kim  00:49

I will let you go first.

Pam  00:51

Okay, so I actually chose this problem because I wanted to play around with the the fact that there was kind of the same numbers happening.

Kim  01:00

Mmhm. 

Pam  01:00

In fact, I've chosen the last couple problems that way that there's kind of this like... Yeah. Because like 90% of 10, there's this implicit 10% hanging around.

Kim  01:10

Mmhm. 

Pam  01:10

So, like there's this 10% and 10. Blah, blah, blah.

Kim  01:14

Mmhm. 

Pam  01:14

So, I'm actually going to find 10% of 10. And 10% of 10, if I divide 100% by 10 to get 10%, then I'm going to divide 10 by 10 to get 10%. So, that's 1. So, 10% of 10 is 1. Right? So, if 10% of 10 is 1, then 90% of 10 is going to be one less than 10, which is 9. That may have been way too convoluted, but that is what I was thinking about today. 

Kim  01:43

You want to know how creepy our brains are sometimes? 

Pam  01:45

Oh, no.

Kim  01:46

You know what I wrote on my paper? 

Pam  01:47

What? 

Kim  01:48

I wrote 9 times 10% times 1 times 10. And I was like...

Pam  01:58

Okay, okay. 

Kim  01:59

And I drew a line to connect the 10% of 10.

Pam  02:03

Mmhm.

Kim  02:05

And I said, "Okay, that's just 1, so 9 times 1 times 1 is 9." And it feels similar to what you...

Pam  02:11

Yeah. That's interesting.

Kim  02:13

Yeah, the pulling out the 10% and the 10 

Pam  02:16

Yeah. Okay, so let me just for fun. If we're thinking about 90% of 10, we could use the commutative property to think about 10% of 90. And 10% of 90 is just 90 divided by 10. And 90 divided by 10 is also 9. So, a couple different ways of thinking about that problem.

Kim  02:32

Yeah.

Pam  02:33

Yeah.

Kim  02:33

Alright, we love scrolling through the feeds and finding out what you do each week, so we hope you join us on MathStratChat and let us know how you think about the problems. And while you're there, comment on everybody else's strategy.

Pam  02:45

We post the problems on Wednesday around 7:00 pm Central. When you tag... No, when you answer. When you answer, tag me and use the hashtag MathStratChat. Or tag, answer. Whatever. 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 because Math is Figure-Out-Able!