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Topic: Need info on the Geometry of Carpentry
Replies: 7   Last Post: Jun 4, 2003 7:50 PM

 Messages: [ Previous | Next ]
 Soroban Posts: 278 Registered: 12/6/04
Great story!
Posted: Jun 2, 2003 4:46 PM

Hello, Aart!

That was a great story. Thank you.

I had similar experiences with my father, an immigrant from Japan
who ran a gift shop in a summer resort.

When I became a math major, I spent my summers working in the family
store. An invoice had an item at \$50 per gross. While I was trying
to estimate its unit price, my father said, "About 35 cents."

I said something like "Huh? What? How...?"

He said, "Multiply by 7."

I did some scribbling (this was in 1962 B.C., before calculators)
and sure enough: 1/144 = 0.006944444 ~ 0.007

I said, "So we multiply by 7 and point off 3 places to the left."

He said, "No, you can SEE where the decimal point goes, can't you?
If it was \$50 for a hundred, they'd be 50 cents each. For 144,
it's a bit less."

I'm retired now, having retired from 38 years of teaching college-
level math. And I still blush over that incident.

Date Subject Author
5/5/03 Casey
5/5/03 Walter Whiteley
5/31/03 Anne Roberts
6/4/03 mark
5/6/03 Art Mabbott
6/2/03 Soroban
6/2/03 Andrew Hume
6/3/03 Earle Jones