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 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  00:20

Okay, so this past Wednesday, our problem was 24/25 minus nine-tenths. And it might be because today is a very special 25th!

Pam  00:34

So, if you celebrate the 25th like Kim and I do, then happy 25th-Christmas-December-ness. Alright, so solve that problem any way you want, and then let's talk about it. Alright, Kim. 24/25 minus nine-tenths. Hmm. Want to go first?

Kim  00:51

Sure. I am going to say that... I'm going to think percents. And I'm going to say that 24/25 fifths is 96%

Pam  01:03

How do you know?

Kim  01:05

Because 25/25 is 100%, and if you back 1/25 then that's 4%.

Pam  01:14

Mmhm. 

Kim  01:15

So, that's 96%. And nine-tenths is 90%. So, I just have 96% minus 90% which is 6%.

Pam  01:25

So, if I forced you to write back in a fraction, your 6% would be? 

Kim  01:29

6/100. 

Pam  01:29

6/100. Okay. Nice. I like it. I got to be honest with you. I think mine is pert near the same, though I did not think percents. So, I'm thinking about money. I'm thinking about 1/25 of $1.00 is $0.04. 

Kim  01:48

Mmhm.

Pam  01:49

And then I was going to back that up from the whole dollar as well. So, that 96 out of 100. And then nine-tenths is like nine dimes out of 10 dimes.

Kim  02:00

Yeah.

Pam  02:00

(unclear) out of 100. And that also leaves me with 6 out of 100. I can't think of a way to simplify 6/100 using coins. Like, I could divide 6 by 2 to get 3, and divide 100 by 2 to get 50. I guess if it was a $0.50 piece. 

Kim  02:19

Yeah.

Pam  02:19

Does that work? 6 out of 100. I don't think so. No, because you're just dividing by 2. You're not really thinking about...

Kim  02:27

Yeah.

Pam  02:28

$0.02. If we had a... What they call those a, ha'penny? No, that's a half a penny. Didn't there used to be a $0.02 piece in... 

Kim  02:35

I don't... Maybe in other countries. I don't know. $2.00 bill, we have.

Pam  02:39

Okay, so it was $6.00 out of $100, and you had... There you go.

Kim  02:43

Three $2.00 bills. Yeah. 

Pam  02:44

Yeah, if you had three $2.00 bills out of fifty $2.00 bills. Do you know... You might find this funny. So, I have 8 siblings. And when any of us... Including all the grandkids. I think there are 39 grandkids. (unclear).

Kim  02:57

Wow! 

Pam  02:58

Mmhm, because my parents are crazy and cool. When any of us have a birthday, my mom sends a $2.00 bill. That's like our birthday present. So, $2.00 bills are not out of the realm of... 

Kim  03:10

Yeah, I got that a lot as a kid too. (unclear).

Pam  03:12

There you go. Well, I get them now as a little bit older of a kid.

Kim  03:15

(unclear) Alright, we can't wait to see every week what you do to solve these problems. Join us on MathStratChat and let us know how you think about them. And then comment on each other's strategies. 

Pam  03:27

We post the problems on Wednesdays at 7:00 pm 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. And, ya'll, if you're actually listening to this podcast as it dropped on Christmas, Merry Christmas! We love having you as part of the Math is Figure-Out-Able movement because Math is Figure-Out-Able!