A rectangle has its length and width in the ratio 5:4. If the area of the rectangle is 180 cm², what is its perimeter?

Explanation

Let the length be 5x cm and the width be 4x cm. The area is given by length × width = 5x × 4x = 20x² = 180. Solving for x², we get x² = 9, so x = 3. Therefore, the length is 15 cm and the width is 12 cm. The perimeter is calculated as 2 × (length + width) = 2 × (15 + 12) = 2 × 27 = 54 cm.