The length, breadth and height of a cuboid are 15 cm, 12

Solution

Length = 15 cm, Breadth = 12 cm, Height = 11 cm The total area of the four side faces of cuboid = 2h(l + b) The total area of the four side faces of cuboid = 22 × 27 = 594 cm² Now, converting percentage to fraction to make calculation easy Length after decrease = 15 × 14/15 = 14 cm Breadth after increase = 12 × 13/12 = 13 cm Height (no change) = 11 cm ⇒ The total area of the four side faces after change in length and breadth = 2 × 11(14 + 13) ⇒ The total area of the four side faces after change in length and breadth = 594 cm² ⇒ Change in total area = 594 – 594 = 0 ∴ No change in the total area of the four side faces.