The area of a projected picture on a movie screen varies directly as the square of the distance from the projector to the screen. If a distance of 20 feet produces a picture with an area of 68 square feet, what distance produces an area of 140 square feet? Round to the nearest tenth of a foot.

Note: if 4=2, then 140=120 feet, and if 8=8, then 68=68 feet