From another website forum by Zea mays: Just curious to see who can get it. I have no clue, but will post the answer from the website. "I recently came across this transportation/math problem for Russian elementary school students (ages ≈ 12 years). I've changed the problem somewhat miles for kilometers, etc.): Two Russian cities, A and B, are 500 miles apart. At the crack of dawn, Person A leaves city A and drives to city B at a constant speed. At the same time (sunrise), Person B leaves city B and drives to city A at a constant speed. They take the same highway and pass each other at 12 noon without stopping. Person A arrives at city B at 4:00 pm. Person B arrives at city A at 9:00 pm. What time was sunrise? I would bet that 75% of American six-graders would have trouble with this problem. We are falling behind in math and science, folks. More than half of the undergraduate physics majors at the University of Chicago are from south-east Asia, and I'm sure that is true of other science universities in the U.S."