Old weather records challenge (Michael Marcotty)
This July was the warmest ever recorded. What is the probability of that happening just by chance, as opposed to a long-term weather trend?
If records have been kept for 100 years, the random probability that July 1998 would be the hottest is 1 percent. The probability that it would be the hottest or the coldest is 2 percent; the probability that some month of 1998 would be the hottest or coldest is greater.
Oldest math problem solved
Last month Thomas Hales, a professor of mathematics at the University of Michigan, announced a proof of a 400-year-old math problem. He proved that the most efficient pattern known for packing identical balls really is the best.
New Mount Everest challenge
Although Mt. Everest, at 29,028 feet above sea level, is the highest mountain in the world, it is not the farthest from the center of the earth. The earth's bulge at the equator pushes Chimborazo in Equador, at 20,561 feet above sea level, farther. (How much?) Now suppose you run a water pipe from Everest to Chimborazo. Which way would the water flow?