A person jogged 10 times along the perimeter of a rectangular field at the rate of 12 kilometers per hour for 30 minutes. If field has a length that is twice its width, find the area of the field in square meters. Choose the correct option:
A) 10,000 square meters
B) 20,000 square meters
C) 30,000 square meters
D) 40,000 square meters
E) 50,000 square meters
Let us first find the distance d jogged   distance = rate ? time = (12 km / hr) ? 30 minutes   = (12 km/hr) ? 0.5 hr = 6 km   The distance of 6 km corresponds to 10 perimeters and therefore 1 perimeter is equal to   6 km / 10 = 0.6 km = 0.6 ? 1000 meters = 600 meters   Let L and W be the length and width of the field. The length is twice the width. Hence   L = 2 W   The perimeter is 600 meters and is given by   2 (L + W) = 600   Substitute L by 2 W   2 (2 W + W) = 600   Simplify and solve for W   4 W + 2 W = 600   6 W = 600   W = 100   Find L   L = 2 W = 200   Find the area A of the rectangle   A = L * W = 200 * 100 = 20,000 square meters   correct answer 20,000 square meters
<result>B</result>
A person jogged 10 times along the perimeter of a rectangular field at the rate of 12 kilometers per hour for 30 minutes. If field has a length that is twice its width, find the area of the field in square meters.