Find the lateral area of a life raft in the form of a regular pentagonal pyramid if the slant height is 17 ft. and one edge of the base is 15 ft. How many persons could be accommodated if a person occupies a space of 8.5 sq. ft.?
1. Draw a rough sketch.
2. Let e denote the edge of the base, the slant height.
Calculate the radius r of the circumscribed circle:
3. The area of a regular pentagon consists of 5 isosceles triangles with the base e and the radius as the other legs.
Divide by 8.5 to answer the question.
3. The lateral area consists of 5 isosceles triangles with the base and the height .