A harvest festival machine presses apples into cider at a constant rate: it takes 4 minutes to press 1 gallon of cider. If 3 identical machines operate simultaneously without stopping, how many total minutes will it take them to press 15 gallons of cider?
20 minutes
3 machines working together press 3 gallons of cider every 4 minutes (or 0.75 gallons per minute). To reach 15 gallons, they need 15 / 3 = 5 cycles of 4 minutes, which takes 20 minutes.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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