A train travels 60 miles in one hour. For the first half hour, it travels at 40 miles per hour. How fast must it travel during the second half hour?
80 miles per hour
In the first half hour at 40 mph, it travels 20 miles. To travel 60 miles total in 1 hour, it needs to cover 40 miles in the remaining half hour, requiring a speed of 80 mph.
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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