A rope ladder hangs over the side of a docked boat, with its rungs spaced exactly 25 centimeters apart. At low tide, exactly 4 rungs remain above the water line. If the tide rises smoothly at a rate of 50 centimeters per hour, how many rungs will be above the water after 2 hours?
4 rungs
Because the ladder is attached to the boat, the boat and ladder rise together with the incoming tide. The water level relative to the rungs does not change at all.
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: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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