A rectangle's area is three times larger than that of a square. The rectangle's length measures 40 cm, and its width is 1.5 times the side length of the square. What is the length of the square's side in centimeters?

Explanation

Let the side of the square be x cm. Then, the breadth of the rectangle = (3/2) * x = 1.5x cm. The area of the rectangle = length * breadth = 40 * 1.5x = 60x. The area of the square = x^2. Given the rectangle's area is three times the square's area: 60x = 3x^2. Simplifying: 3x^2 - 60x = 0 => 3x(x - 20) = 0. So, x = 0 or x = 20. The side length of the square is 20 cm.