A rock was dropped from a platform on a tower 57 feet above a lake. The rock landed on the bottom of the lake which was 20 feet under the surface of the lake. Where was the rock when it had fallen halfway?

38.5 feet above the lake
37 feet above the lake
18.5 feet above the surface of the lake
47 feet above the lake

Question

A rock was dropped from a platform on a tower 57 feet above a lake. The rock landed on the bottom of the lake which was 20 feet under the surface of the lake. Where was the rock when it had fallen halfway?

38.5 feet above the lake
37 feet above the lake
18.5 feet above the surface of the lake
47 feet above the lake

richyw · Answer

how far did the rock fall in total?

anonymous · Answer

idk @richyw

richyw · Answer

here. I sketched a picture (and even added colour)

richyw · Answer

how far is it from the top of the tower to the bottom of the lake?

anonymous · Answer

Add 57 and 20 together and what do you get?