A closed wooden box of uniform thickness has length, breadth and height 20cms, 16cms and 12 cms respectively. If the thickness of the wooden block is 2 cms. What would be the inner surface area of the box?
Inner length = 16 cm Inner width = 12 cm Inner height = 8 cm Inner surface area = 2(lb + bh + lh) = 2 (16 × 12 + 12 × 8 + 8 × 16 ) = 2 (192 + 96 + 128) = 2 × 416 = 832 cm2.
