The Great Speedster roller coaster runs 3 trains every 10 minutes. At that rate, how many trains does the roller coaster run every hour explain how you determined your answer

Two cars run at constant speeds around a one-mile racetrack. If the cars circle the track in the same direction, the faster car passes the slower car every 10 minutes. If the cars circle the track in opposite directions, the cars meet every 30 seconds.