The perimeter of a square is 120 cm. The length of a rectangle is two times the side of the square. The perimeter of the rectangle is 156 cm. What is the difference between the areas of the rectangle and the square ?

Correct option is D

Perimeter of the square = 120 cm
Side of the square = 120/4 = 30 cm
Length of the rectangle = 2 = 60 cm
perimeter of the rectangle = 2(60 + b) = 156
120 + 2b = 156
2b = 36
b = 18 cm