Being a big geek who works at math problems for recreation, I was excited when my wife enrolled in a math class at a local college. My plan was to read up the material and work the same exercises as she was assigned. It would be fun for both of us and I'd learn something, too. So far, though, it hasn't been working. I have a job, two kids, something resembling an obsession with American politics, an unambiguous obsession with baseball, especially the fortunes of the Minnesota Twins, and, lately, in my spare time, I've been progressing, at the rate of about ten pages a day, through Benny Morris's *Righteous Victims: A History of the Zionist-Arab Conflict, 1881-2001*. No time for my wife's math.

Still, I'm dimly aware that the first lessons of the class involve the Gaussian elimination and the solution for systems of linear equations. The name comes from the inventor, or discoverer, of the method, Carl Friedrich Gauss, one of the great mathematicians of all time and a child prodigy. Once, a math instructor related to a class in which I was enrolled the following anecdote. In what we call elementary school, the very young Gauss, bored during an arithmetic lesson, was raising a disruptive ruckus. Finally the exasperated teacher said, "Carl, I don't want to hear another peep until you've summed the first hundred integers and given me the answer." Gauss, who had been loudly tapping his pencil on his desk, kept it up. "Carl, I mean it!" The boy answered loudly above the sound of his thumping pencil, "Five thousand and fifty!"

The teacher of course thought the boy would have to do 1 + 2, then add 3 to 3, then 4 to 6, then 5 to 10, which gets tedious fast. Plus you'll probably get confused and make a mistake before you make it into the thirties. But the young Gauss must have realized that 1 + 2 + 3 + 4 + ... + 99 + 100 may more simply be thought of as (1 + 100) + (2 + 99) + (3 + 98), etc.--that is, it's the same as a hundred and one fifty times. A boy clever enough for such an insight is also going to be sufficiently clever to do the multiplication in his head: 101 x 50 = (100 x 50) + 50 = 5050.

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