Saturday, July 15, 2017

Maths!

Proof without actual numbers. Just knowns and a piece of string.

My aquarium is scratched and I will replace it. That is the mathematic problem at hand.

Found a nice one on Craigslist for a good price. I can just go there and buy it. But I want to keep my base for it. So the new tank's dimensions must match. I told the guy the numeric dimensions, because that's how those things are communicated, and he texted back saying he'll measure tomorrow. Today. And I haven't heard back yet. Maybe he doesn't have a tape measure or a ruler.

Pffft. Who cares about exact scientific measurement by numbers in inches?

We're talking about a 50 gallon aquarium so its dimensions are largely intuitive. It's going to be big. We're checking to see the tank its long, tall and narrow and not squat and wide. And we're checking to make sure it will fit my base exactly. Any differences between tanks will be a matter of only a few inches in either direction. So we want the proper ratio of sides, without caring about precise numerical measurements. We can act as if inches don't even exist. But ratios do. So no need for a tape measure or ruler.

I texted back suggesting he could use a piece of string to confirm. The numerical dimensions in inches are 48"x12"x18".

Beautiful numbers, don't you think?

That's 4 to 1 to 1.5

Knowing that solves everything. A short string can be pulled to shortest measurement, the width, presumably, hopefully, 12 inches for his tank.

Then that string length can be used to pinch off 4 sections of the length, presumably 48 inches.

Proof, right there.

If the top and bottom are 4:1 then the height must be 18 inches.

To prove that too, the seller can use the short string for a new ratio. Width is presumably 12" and height is presumably 18" or  2x6 : 3x6.

So the short string can be folded in half and used to pinch off three sections of height.

QED, right there. Ta-daaaaaah. Graciously bows.

Conversely, a long piece of string can be pulled off to the full length, then folded in half twice, for 4 folded lengths, and that used to compare with the width.

And that same 4 folded string halved again (for 6 inches presumably) and used to pinch off 3 sections up for the tank's height for 18 inches presumably.

If that works then his tank will definitely fit my base. And if that doesn't work then the tank will not fit my base.

Now this right here is the sort of thing they teach you in school when you pay attention and in books when you read them. But what they don't teach you is that you don't have to go digging around in your toolbox for a tape measure all the time thinking that is your only option and comparing numbers all over the place holding them in mind and confusing you when a piece of dental floss is sitting right there.

I'm pretty sure this is how cavemen and cavewomen confirmed their aquarium dimensions.

6 comments:

Eric the Fruit Bat said...

The problem is: There was that caveman guy who invented the pirate's treasure chest that filled up with air and then released a huge bubble, and everybody made fun of him, and so the guy who had already invented the Ferris wheel that keeps spinning around because of all the little air bubbles (but who never told anyone for fear they would all laugh at him), . . . well, . . . he never told anyone.

And it would be a real, real long time before things would catch up to where they should have been all along.

THE END.

Sixty Grit said...

Given a 48" width I might be inclined to go with a 29.6" height. The other dimension on the tank might as well be 12" - going with the natural 18.3" as the third dimension might make the tank too large for the room.

Chip Ahoy said...

That would be something like a 75 gallon tank.

Rabel said...

1 U.S. Gallon = .133681 cubic feet

48"x12"x18" = 10,368 cubic inches / 1728 [cubic inches in a cubic foot] = 6 cubic feet.

6/.133681=44.882967661821799657393346848094 gallons.

You was robbed.

Sixty Grit said...

You don't have to fill it with water.

At 8.3 pounds per gallon of water a full 75 gallon tank would weigh 622.5 pounds, exclusive of the weight of the tank and associated equipment. Back when I knew something about building codes the load limit for residential buildings was something like 100 pounds per square foot, so if the base is a bit over 6 square feet then maybe your dwelling will not collapse under the load.

Won't someone please think of the fish?

Chip Ahoy said...

I invented that that bubble treasure chest when I was ten.

Except mine was clam.

I used a real clam and drilled 4 holes for two makeshift wire hinges and another larger hole for an air tube running under the gravel. Put a valve on the air tube and turned it down real low. So the thing burped every few minutes.

I loved my little air clam.

And then whadda know. Similar things were marketed.

You know what?

I realized yesterday that just as aquarium gardening has swept the whole world by Takashi Amano's insights and by his quiet obsessions to include species gathered from across the entire globe, so too have the fish.

At ten I had a book of available fish species, and now reading the youngster's comments on tropical fish stores I must open new browser windows as I read to see what they're talking about. I just don't recognize any of them. A whole new world has opened.

It's making me fascinated all over again. It's like being reborn into a newly refreshed hobby. And it entails every aspect from gravel, filter, CO2, and lighting.

Similar to hieroglyphics. Everything that you learn must be reconsidered mere years after as new information and new insights keep rolling in. It never stops.