I avoid math as much as possible, but when there’s arithmetic to be done I have a calculator handy. Surprisingly, they still teach 6th grade math as if all calculators will spontaneously combust in 2015, which is why Finn is learning the tedious process of dividing complicated numbers by other complicated numbers.
There are infinite combinations of complications that I shudder to contemplate, for I’m sure they await Finn (and thus me) in the future. Dividing one fraction into another! Dividing a square root by an integer! Dividing percents! Dividing a negative number by another negative number, as if that ever happens in real life!
You notice I haven’t even reached the part where you start solving for X.
Finn needed help with his homework the other night, and Bill, the default, was out. I dispatched Finn to the shower so I would have plenty of time to work out the kinks in my teaching method.
The topic du jour was dividing decimals:
I knew exactly what to do as a first step; I rewrote the equation into proper division form:
I pondered this for a few minutes but the decimals were in my way, so I proceeded to the logical next step: a frantic call to the Voice of Reason. She majored in Economics and I’ve been calling her about issues raging from mathematical to culinary for more than twenty years.
“Have y’all already covered dividing a decimal number by another decimal number?” I asked.
“That’s what I was bitching about in Jazzercise last week,” The Voice said. “It’s a pain in the ass. Don’t tell me you’re helping Finn with math homework. Where’s Bill?”
It’s reassuring to have someone know you so well that she can instantly tell your husband is missing based on a phone call about homework.
“He’s in a deposition that’s running late. And I’m not completely incompetent in math, although this is really stretching my brain,” I said. “I remember something about flipping fractions over to divide them, so I was thinking dividing decimals would be a snap because there’s no gymnastics.”
“That’s true, you don’t have to flip anything,” The Voice said.
“Okay, so I have the big number in the hut and the smaller number outside the hut, but they both have decimals. Don’t I move them somewhere?”
“Yes, wait…” I listened as The Voice shuffled a piece of paper around and drew on it.
“You move the decimals over to the east as far as they will go, and then you solve the problem like you normally would,” she said.
“The east like the right?”
“Well, that stinks. Because if you moved them the other way, we could teach it by singing it like the Beyonce song: ‘To the left, to the left, pick up the dot and move it to the left,'” I sang.
“Yeah, that’s a big bummer,” The Voice agreed drily. “Now that you’ve moved the dot over, you just divide the numbers out the way you normally would, and then you put the dot– I mean the decimal– God, you’ve got me saying it too, back in place.”
So I moved the decimals to the east:
but I stuck a dot on the roof of the hut so I’d have some idea where the decimal would be returned at the end of the procedure.
I heard the shower shut off. Finn would be coming soon, so I had to be ready to teach.
I reviewed my notes and started working the problem out by hand. It was arduous, what with all the multiplying and carrying (which I still do on my fingers) and subtracting, so I got my calculator out and figured out that the answer would be
That was a hell of a number to contemplate sober. Solving it without technology would take all night and several sheets of paper even before I starting instructing Finn.
Worse, this answer didn’t exactly match the work I’d already done; I was sweating and I had come up with 1.335 so far. Clearly The Voice and I had a miscommunication as to where the decimal was going when it went back into the equation.
I poured a glass of wine and went back to the problem, this time ignoring the decimals entirely, and that’s how I ended up telling Finn to do it, too, for lack of a better option.
We came up with 133514 and then Finn and I had to figure out how to put the decimal in the right spot in the answer.
We ended up using the “sort of” method which they actually teach in third grade, only they call it “guesstimation.” Finn and I decided that 42.7 was sort of like 40, and 568.77 was sort of like 570, so the answer should be sort of like 13ish.
It worked for us, and I went to bed happy, since I knew we’d gotten the problem right.
Except we hadn’t. Finn came home the next afternoon and said we’d gotten points off for failing to follow directions. I looked down guiltily, wondering how my calculator use had been discovered. I’d been careful to put the calculator away before Finn ever came in the room.
It turned out that the instructions said to round to the nearest tenth, so our exuberant answer of 13.3514 looked downright suspect.
Ahh, well. Tis better to have divided well than never to have divided at all, I suppose.
A year ago in My Tiny Kingdom: Crime & Punishment