A train leaves Station A traveling at 60 mph. One hour later, a faster train leaves Station A heading in the same direction at 90 mph. How many hours after the second train departs will it catch up to the first?
2 hours
The first train has a 60-mile head start. The second train closes the distance at 30 mph (90 - 60). Closing 60 miles at 30 mph takes 2 hours.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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