How many of us skated through elementary school without ever really learning our times tables? I know I’m not alone in this. Especially since the advent of electronic cash registers and hand-held calculators, we haven’t really needed the ability to do even basic math in our heads, have we?
But there I stood at the office supply store yesterday, trying to figure out whether buying paper by the ream was cheaper than buying it by the box. A ream = 500 sheets, and at least I know my five-times tables, but I kept thinking the math in my head must be wrong if it was coming up cheaper to buy five reams, rather than a box full of five reams of the same stuff. So I called up my trusty cell phone calculator, and sure enough, I was right. Those tricksters! Playing on my belief that buying in bulk is always cheaper! Hah! I showed them, and I saved myself five dollars.
But it got me to thinking about what I’ll do after the global climate change cataclysm. You’re standing in the flea market, trying to figure out whether it’s more economical to buy your moldy rice by the scoop or the sack. Your cell phone is long dead. What are you going to do? Just do the rough math as best you can? Or do you make wild guess and hope for the best?
Then how do you know if they’ve given you correct change if there’s no electronic cash register to show what you ought to expect? OMG, how do you subtract $17.49 from the twenty you just handed over? Or subtract seven cowries from the large mollusk shell you just handed over in payment?
You have two choices here.
After the cataclysm, swindlers and sociopaths will come out of the woodwork. With the right preparation, you can protect yourself from some of the worst. But you’ll need to be able to count your own change.
Abacus photo by Shenghung Lin