Microwave Math

I write this as PSA for colleagues at my school. I do not expect any of them will stumble upon this post, but all the same: I dedicate this to the few, the proud, and the brave who battle regularly with the microwave in Room 2220.

The New Toy

It showed up on our first day in the new school building: smooth but angular, sleek but hefty. The Summit Commerical 1000SS sat patiently on the counter of our faculty lounge, awaiting the first lunch wave. It was shiny and new, but looked familiar. Utilitarian. There was a panel of buttons with numbers and some key words trailing down the right side of the machine.

I didn’t try it on the first day in the new building, or even the second. A week must have passed with cold lunches — salads, fruits — until one day I brought in a small bag of microwave popcorn as a snack. In my microwave at home, it takes 1 minute and 15 seconds to reach an optimal stage (at least 85% popped, 0% burned). I wasn’t going to risk burning a single kernel in this new microwave, so I decided I’d set it for 1 minute even.

I pressed the 1 and then the 0 for 1:00. The machine beeped indignantly at me. I had disturbed its slumber.

I pressed 6 and then 0, only to be met with the same impatient beeps.

It wasn’t going to be so easy.

The First Experiment

So what happens when you press 1?

Not much. You need to hit start to get the action going. But press 1, then start, and, bam: 10 seconds.

Press 2, then start: 20 seconds.

Press 3, then start: 30 seconds.

I chuckled to myself. It was all so simple. I hit 6, then start.

1 min 30 seconds.

Man.

The Second Experiment: All The Programs

1 –> 10 sec

2 –> 20 sec

3 –> 30 sec

4 –> 45 sec

5 –> 1 min

6 –> 1 min 30 sec

7 –> 2 min

8 –> 2 min 30 sec

9 –> 3 min

0 –> 3 min 30 sec

I will confess that these times made a fair amount of sense to me as landmark times. How often do we put in things for other times? Then my son came to my mind. He thinks that the instant oatmeal has the best texture when microwaved for 1 min 40 seconds in our home microwave. At 1 min 30, it’s slightly soggier, and at 2 min it’s firmer. So would we just need to monitor this microwave to optimize textures?

The Third Experiment: x2

I confess: by now, I had posted on Twitter. Christopher Danielson was quick to join in with #MicrowaveMath. My popcorn was popped, but there were more experiments to do.

This microwave didn’t have ‘soften’ or ‘melt’ buttons, but now I was intrigued by the x2 button.

Using the programmed’ would get me my desired 60 seconds, but so would the 3 button and the x2 button. What other times had multiple pathways?

Pressing 1 and then x2 would double 10 seconds, for 20 seconds — equivalent to the programmed 2.

Pressing 4 and then x2 would double 45 seconds, so 1 min 30 seconds. I could also get that by pressing 6.

Program	Time	After x2	Does this match a programmed time?
1	10 sec	20 sec	yes (2)
2	20 sec	40 sec	no
3	30 sec	60 sec	yes (5)
4	45 sec	90 sec	yes (6)
5	1 min	2 min	yes (7)
6	1 min 30 sec	3 min	yes (9)
7	2 min	4 min	no
8	2 min 30 sec	5 min	no
9	3 min	6 min	no
0	3 min 30 sec	7 min	no

It would be kind of nice to have a half button (30 seconds –> 15 seconds), but, honestly, unnecessary. At that point, just stay close and monitor the food. That’s what I recommend to all of you, my dear colleagues. (Ha! If any of them found this blog, they definitely abandoned it by the time I inserted the table. It’s just you and me now, reader.)

Experiment #4: Powerrrrr

Hitting ‘power level’ allows you to scroll through three different settings (hi, med, def, or what I assume are high, medium, and defrost). This is the only setting that allows multiple number buttons to be pressed. This also seems like the way to input specific times!

Although I am now realizing that I am making assumptions about the microwave, and that this is absolutely not a microwave I can make assumptions about. If I input 74 seconds, will it run for 1 minutes and 14 seconds? If I input 114 will it ALSO run for 1 minute and 14 seconds, or will it go for 114 seconds, which is 1 minute and 54 seconds?

Microwave Fluency

My biggest conclusion about this microwave is that it is ill-suited to a school’s faculty lounge, and, after I hit publish on this post, I’m going to post a cheat sheet in honor of everyone that I have seen ‘guessing and checking’ with a hungry exasperation. Our lunch breaks are too short for this nonsense.

I have not used the microwave much, but I’ve become remarkably fluent in using the preprogrammed values. This means that I’m much less frustrated when it comes time to heat something for lunch. In fact, it can even be playful, like when using the x2 button. What does this say about fluency in math class? How do we benefit from mathematical fluencies? How do we develop them?

And did I become Microwave Fluent out of curiosity, out of necessity, or out of my drive to be The Smartest? Does motivation matter here? (I say this to downplay the competitive third option here. I swear, this is all for the love of mathematics!)

Functions

Today, I worked with an 8th grader on some additive patterns involving integers.

We were increasing or decreasing by a constant amount, and operating under the assumption that the patterns will continue like that.

But not all patterns are so nice and linear. We could model the growth of time with a piecewise function.

Always More Questions

Christopher asked me about some mysterious numbers at the top, and I haven’t figured it out yet.

Yes, I could read the manual, but I’d much rather go Full Inquiry on this one. (Because I’m motivated by curiosity and a love of mathematics, right?)

I received a few other questions on twitter, like:

Christopher also posed his own Microwave Trivia, which, while not mathematically, did stump all of us.

Spoiler, because you’re never going to guess it:

• Butter
• Ice Cream
• Cream Cheese
• Frozen Juice

In summation: microwaves are bizarre. My Algerian in-laws think that Americans are weird for relying on them so much when we have other ways to heat food that Look Like They Give Cancer Less, and, as a bonus, have superior taste and texture. That said, I look forward to more experiments in room 2220.