Saturday, September 23, 2006

Math Simplified: a fresh take on multiplication

Thanks to the folks at 37signals for reposting this blurb on simplified arithmetic for products of two (or more) two-digit numbers.

(The original article was run in the Chicago Tribune, registration required.)

Take a minute to walk through this technique:

**Note: the following material is my original work, not a re-posting.**

The grid approach is not without that pesky requirement to "carry" ones. It is merely a re-arrangement of traditional multiplication. (Trust me, it is: the "proof" is too nerdy to endure!)

The C-trib illustrators inadvertently cause a pitfall for students of the new technique when they start diagonal addition from the left. One small adjustment solves the discrepancy: begin addition from the right.

Ask yourself: can you think of a combination of two 2-digit numbers for which at least one of the diagonal sums is greater than 10? If you can, you've just demonstrated to yourself the need to begin diagonal addition from the right, carrying 'extra' ones leftward, as is with the traditional approach. See my illustration below:

The first result occurs when diagonal addition begins at the left; illustrated at right is the intended result, having carried the ones: 78 x 59 = 4602.

Continuing the algorithm just a little farther into application, we see that it still works when applied to three-digit products (example, 362 x 147 = 53214):

And, with nerdy satisfaction, I proudly report to all two of my readers that I did this just for fun!

My favorite Calculus professor (pictured) taught us about a Latin abbreviation commonly used to signify the close of a proof: Q.E.D. (Quod Erat Demonstratum). I much prefer the mnemonic device he taught us to remember it, tongue in cheek: "Quite Easily Done."

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Friday, September 22, 2006

Breast Ambassador

Apparently I'm just six years on the uptake, but for those of you who also haven't heard of this... There's a group in Canada that produces an annual calendar entitled "Breast of Canada." The calendar site claims: "The Breast of Canada calendar is about health. Maintaining and improving your health and cultivating a positive body image stimulates a higher quality of life... Net proceeds for the 2007 edition will be directed to the Canadian Breast Cancer Network."

Finally, my favorite is the list of ten steps to becoming a Breast Ambassador:
1. Buy two Breast of Canada calendars. Put one up in a prominent place in your home or workplace. Give one to someone you love. The calendar is an affordable tool for change. It will inspire conversation.
2. Use your voice.
3. Make friends with your own body - Touch your breasts. [My note: this is to encourage self breast exams.]
4. Avoid blaming and complaining about "them" and try reclaiming "you."
5. Turn off your television for a straight 24 hour period and engage your imagination instead.
6. Be brave - It takes courage to change the world. But it's fun to roar like Tarzan.
7. Smile and use your sense of humour - People don't like to be hit over the head, but we can all use a good laugh.
8. Notice your own behavior and how you contribute to our society's attitudes about women's bodies.
9. Realize that you can completely change the world with your effort. Always give yourself a pat on the back.
10. Become a Breast Friend of the Breast of Canada calendar.

I'm excited about ordering my calendar. Let me know in comments if any of you does the same.

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Monday, September 18, 2006

American English: taxonomy

This is fitting; I never can manage to escape that little bit of northern-Minnesotan lilt. What do you mean there is more than one pronunciation of "route"?!

Your Linguistic Profile:
75% General American English
10% Upper Midwestern
5% Dixie
5% Yankee
0% Midwestern

I got this "Blog Thing" via Notes to Self, who sometimes thinks she's speaking into a void.

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Tuesday, September 12, 2006

California, reception, reunion

Derek, Irena and me

Took a trip to California this last weekend to celebrate and honor my cousin Derek's marriage at a small reception. I felt so priviledged to be invited; our reunion had been fifteen years coming. He was my childhood best friend, outside of siblings of course, and that connection came rushing back in a few precious instants of conversation and reflective walks. My parents were there, too, along with a number of other family members I hadn't seen in years. San Francisco offered periods of relaxation, more out of inability to do anything else than lack of a to-do list. I took this picture of us just after leaving the chocolate festival at Ghirardelli Square. Cheers.