A nonstop train leaves Moscow for Leningrad at 60 miles per hour. Another nonstop train leaves Leningrad for Moscow at 40 miles an hour. How far apart are the trains 1 hour before they pass each other?
Answer
The trains will be 100 miles apart.
In 1 hour, one train will travel 60 miles and the other train will travel 40 miles. Together, they will cover 100 miles.