James cast a lure from 8 feet above the sea level to a depth

James cast a lure from 8 feet above the sea level to a depth of 22 feet under water. The lure was taken down by a trout another 15 feet. James reeled in the fish so that it was pulled up vertically 30 feet. At that point the line snapped and he lost the fish. At what depth was the fish when the line snapped?

Solution

If the lure dropped to 22 ft. below the surface and was taken down an additional 15 ft. then it is now at (22+15=37) 37 ft. below the the surface.
Next, James reeled the lure and trout straight up for 30 ft. so it is now (37-30=7) 7 ft. below the surface. At which point the line snapped and the big one got away.
So the fish was at a depth of 7 ft. below the surface.