Snapshot of Middle America

I’m visiting my parents in Kansas this week. It’s been a while since I’ve been been back and the contrast to the Bay Area couldn’t be greater. It’s hot; there are lots of bugs; drivers take their time in making decisions; going out to eat means a trip to Olive Garden. And since I was last here about a year ago, it seems like the population has aged markedly. My brother Mark works on a county board to bring accessible public transit to the masses, and he confirmed. Johnson County is getting old.

This is a picture from the gloriously cluttered house that my parents call home. When I pointed out the irony to my mom, she laughed and said, “Yup. I sure do like to read about it.” (Zoom in or click on the pic to see what she’s talkin’ about.)

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Sample Problems (and Solutions) from the 2009 International Mathematics Olympiad

Earlier this month, high school students from around the world gathered in Bremen, Germany to test their math skills in the 50th annual International Mathematics Olympiad. If you’re interested in the type of problems that high school students can solve using only algebra, geometry, number theory, take a look:

Let n be a positive integer and let

be distinct integers in the set {1, . . . , n} such that n divides for i = 1, . . . , k − 1. Prove that n does not divide .

For a complete list of problems and solutions, go here.

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