Lateral Thinking · Ages 10–12
Riddle #112
A rope ladder hangs over the side of a boat floating in the ocean, with 6 rungs showing above the waterline. Each rung is 20 cm apart, and the tide is rising at 20 cm per hour. After 3 hours, how many rungs are still showing above the water?
You solved this one before
Open-ended riddle: think it through, then reveal the answer.
Answer: Still 6 rungs
The boat floats, so it rises with the tide right along with the water — the ladder rises too, and the same 6 rungs stay above the waterline.