Question 24
A certain semi-circular tunnel covers 2 cemented lanes. Beyond the lanes are the gutters whose widths of 2 feet each extend up to each of the edge of the tunnel. The maximum height of vehicles that can pass through the tunnel while travelling along the edge of the lane is 7 ft. What is the total width of the tunnel?
Convention: use the outer lane edge adjacent to a gutter.
Convention: use the outer lane edge adjacent to a gutter.