A few weeks ago I posted the U.S. team for this year’s International Math Olympiad, held in Santa Marta, Colombia, July 18th to 28th. Here’s another picture of our team, this one from the opening ceremony.
The Olympiad has now wound up. You can download the six challenge problems here; just choose a language from the 2013 box.
Each problem is worth 7 points. The number of participants who got 0, 1, 2, . . .,7 points on each of the six problems is histogrammed here. As you can see, the order of difficulty, hardest to easiest, was problems number 6, 3, 5, 2, 1, 4.
Country rankings here. Top ten: China, S. Korea, U.S.A., Russia, N. Korea, Singapore, Vietnam, Taiwan, U.K., Iran.
Individual rankings here. Best performances—41 out of the 42 possible points (7 points for each of 6 questions, remember)—were by Yutao Liu of China and Eunsoo Jee of S. Korea. You can insert your own Asian-mother joke here: “What happened to the missing point? . . .”
Best performance by a non-East Asian was 38 points by Omri Nisan Solan of Israel.
I notice all three got their 35 points by skipping one question completely—one of the two hardest in every case—and getting perfect scores on the others.
This smells like strategy to me: the team coaches saying: “Scan the six questions, figure which one is the hardest, ignore that one and go gangbusters on the other five.” Well, it got them gold medals, so all congratulations to them, and to their team-mates, who gathered another gold and two silvers.
The IMO is humbling and a bit depressing for this old math geek. Back in the 1990s I used to work through the problems on an idle weekend. I put one of them into Fire From The Sun (it opens chapter 31).
Well, I just wasted half a day on Problem 1—the second easiest, note. I’ll tackle the others . . . another time.
What I say is, they’re making the problems harder every year. That’s got to be it.
Note that the IMO contestants get 4½ hours for all six problems, average 45 minutes per problem. These are really good young mathematicians here.