Two rectangles, one lying completely within the other. The area between the rectangles is shaded. Two adjacent sides of the larger rectangle are labeled sixty feet and forty feet. The shaded area is labeled four foot border.
Area of larger rectangle = 60 ft * 40 ft = 2400 ft²
Area of smaller rectangle = (60-4)ft * (40-4)ft = 56 ft * 36 ft = 2,016 ft²
Area of the border = 2,400 ft² - 2,016 ft² = 384 ft²