## Wednesday, August 12, 2009

### Money's not just for buying things

BACKGROUND INFORMATION ITEM #1
A few days ago I asserted that math was "A language of counting, measurement, shapes and calculation. A language with precise definitions and specialized terms."

BACKGROUND INFORMATION ITEM #2
TV chef Alton Brown can't bear precious space being occupied by a device that's good for only one thing. I agree. So I don't want any (more) things around that only have one function. We say "Death to Uni-Taskers!"

THE BLOG STARTS HERE
Yesterday we looked into the cost of a cup of tea. I needed a scale to measure the weight of both dry and liquid tea.

At The Mighty AnsMar (home of Excel Math) we have 3 scales. The first is connected to our postal meter (0-5 lbs) and the second stands alone (0-10 lbs). The third is in our warehouse (0-200 lbs) and isn't suitable for tea.

Sadly, the two smaller scales disagreed on the weight of a small item. Disagreed by about 30 percent even after zeroing and resetting. How could I do an accurate measurement?

I needed a reference weight - like in old Westerns, where the clerk puts a brass weight on the scale to balance the pile of gold dust.

But I didn't have one. If I went to the post office, weighed something and labeled it - would I keep it handy? It would be a Uni-Tasker. No. I had to find an item that was consistent, readily available, and whose weight was well documented. Coins.

I thought a one-ounce weight would be useful for calibrating the scale. But none of our coins weigh an ounce. I would need several. A simple group of coins. Too complicated to stack 4 dimes, 3 pennies and a nickel, for example.

At the US Mint I learned that this Louis Braille Dollar Coin is August's Coin of the Month.

I didn't even know there was a Coin of the Month. Or a Braille coin. After looking at all the ways I could spend money on money, I got back on task.

A little division, multiplication and metric/standard unit conversion indicated that I needed quarters.

Knowing an ounce was 28.349 grams, I confirmed the choice of a quarter using a handy comparison table on Wikipedia.

A quarter weighs 5.67 grams so 5 quarters must equal 28.35 grams. Five quarters equal one ounce. Come on, do it with me in your head 5 x .07 = .35 and 5 x .6 = 3 and 5 x 5=25.

VoilĂ ! My standard weight is readily available, always replaceable and easy to stack on the scale. And how about this? A quarter's weight equals a teaspoon of most teas ≈ 5 gm!

Money. Not just for buying things, it's for precisely counting, measuring and calculating. It's for math.

PS - Death to Uni-Taskers.