Question

an open box is made of wood 3 cm thick.its external dimensions are 1.46m,1.16m and 8.3 dm

Answer 1

Given thickness of wood = 3 cm
Length of open box = 1.46 m = 146 cm
Breadth of open box = 1.16 m = 116 cm
Height of open box = 8.3 dm = 83 cm
Inner length, l = outer length – twice width
                           = 146 – 6 = 140 cm
Outer breath = 116 – 6 = 110 cm
Outer height = 83 – 3 = 80 cm [since it is an open box]
Area of inner surface = 2(lb + bh + hl) – lb
= 2[140 x 110 + 110 x 80 + 80 x 140] – [140 x 110]
= 55400 sq cm
Cost of painting inner surface = Rs (50/100) x (55400/100) = Rs 277