Two cyclists start 60 miles apart and cycle straight toward one another, both maintaining a constant speed of 15 miles per hour. A fly starts on the handlebars of one bicycle and flies back and forth between them at 20 miles per hour until the bicycles meet. How many total miles does the fly travel?
40 miles
The cyclists close the distance at a combined rate of 15 + 15 = 30 mph, taking 60 / 30 = 2 hours to meet. The fly flies continuously for those 2 hours at 20 mph: 2 × 20 = 40 miles.
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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