introduced into his novel, Kavenaugh:? This famous puzzle is about a water lily that Henry W. Longfellow introduced into his novel, Kavenaugh:
When the stem of a water lily is vertical the blossom is 10 centimeters above the surface of the lake. If you pull the lily to one side keeping the stem straight the blossom touches the water at a spot 21 centimeters from where the stem formerly cut the surface. How deep is the water?