Math is Figure-Out-Able!
Math teacher educator Pam Harris and her cohost Kim Montague answer the question: If not algorithms, then what? Join them for ~15-30 minutes every Tuesday as they cast their vision for mathematics education and give actionable items to help teachers teach math that is Figure-Out-Able. See www.MathisFigureOutAble.com for more great resources!
Math is Figure-Out-Able!
#MathStratChat - February 5, 2025
In today’s MathStratChat, Pam and Kim discuss the MathStratChat problem shared on social media on February 5, 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.
Twitter: @PWHarris
Instagram: Pam Harris_math
Facebook: Pam Harris, author, mathematics education
Want more? Check out the archive of all of our #MathStratChat posts!
Kim 00:00
Hey, fellow mathers! Welcome to the podcast where Math is Figure-Out-Able. I'm Kim.
Pam 00:06
And I'm Pam.
Kim 00:06
And this episode is a MathStratChat episode where we chat about our math strategies. Every Wednesday evening, Pam throws 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.
Pam 00:20
Alright, this Wednesday, our math problem was four-fifths times three-fourths. How would you solve this problem? Pause. Solve the problem any way you want. The problem is four-fifths times three-fourths. Go.
Kim 00:33
Okay.
Pam 00:35
Four-fifths times three-fourths.
Kim 00:37
I'm going to go first.
Pam 00:39
Alright, go.
Kim 00:40
I'm going to actually go three-fourths of four-fifths.
Pam 00:45
Turkey.
Kim 00:46
Haha. And three-fourths of 4 is 3. So... Yeah.
Pam 00:51
How do you know that? (unclear).
Kim 00:52
Well, I'm going to say, it's actually 75% I can't not look at. It's always 75%. So, 75% of 4 is 3, so it's three-fifths.
Pam 01:04
I mean, I'm not sure that... So, how do you know three-fourths of 4 is three? Or, how do you know 75% of 4 is three? Like, is that too... Can you talk about how you know that?
Kim 01:12
Because there's only 4, and 75% is... (unclear). I mean, I don't... I'm not picturing one 25% and scaling up. I'm not picturing all of it minus a quarter of it.
Pam 01:26
Okay. (unclear).
Kim 01:27
I'm just thinking it's 3 out of 4.
Pam 01:29
Yeah. Are you picturing 4 chunks? And 3 out of 4 means 3 out of those 4, so it's got to be three.
Kim 01:34
Yeah, I guess so.
Pam 01:35
Maybe that's too easy. I don't know. Okay, cool. Let's see if I can come up with anything different.
Kim 01:43
Do you want? You want to do... You want me to suggest something?
Pam 01:48
You're going to help me? I mean, one thing I could do is think about four 1/5s times three 1/4s.
Kim 01:55
Mmhm.
Pam 01:56
And then commute.
Kim 01:58
Yeah.
Pam 01:59
So, I could have four 1/4s times three 1/5s. And four 1/4s is 1 times three 1/5s is three-fifths.
Kim 02:09
Yeah. I think this is a really nice example of a problem where using commutative property is super slick.
Pam 02:15
Super slick. You might be interested, teachers, to know why we are not just slashing and burning.
Kim 02:21
Ugh.
Pam 02:21
You know.
Kim 02:22
"Just flip them! Flip the numerator!" Ugh.
Pam 02:24
I mean, yeah. There's so many times that we've got students that just apply the rules at the wrong time that we'd like to keep kids thinking and reasoning, and so that's why. Yeah. Alright, ya'll, we can't wait to see what you do each week. Join us here on MathStratChat, and let us know how you think about the problems, and comment on each other's strategies.
Kim 02:43
Yeah, Pam posts the problems on Wednesday at 7:00 pm Central ish. When you answer, tag her and use the hashtag MathStratChat. Then join us here to hear how we're thinking about the problem. We love having you a part of the Math is Figure-Out-Able movement.
Pam 02:57
Because Math is Figure-Out-Able. Ba dum tss.