The outer dimensions of a closed wooden box are 10 cm by 8 cm by 7 cm Thickness of the wood is 2 cm. Find the total cost of wood to make box, if 1 cm3 of wood cost Rs.2.00.
The outer dimension of Closed window are 10 cm; 8 cm; 7 cm
8 cm−2 cm=6 cm
7 cm−2 cm=5 cm
Volume of the cuboid =length×breadth×height
=(10 cm×8 cm×7 cm)−(8 cm×6 cm×5 cm)
=560 cm3−240 cm3
=320 cm3
⇒ The total cost =320×Rs. 2
=Rs. 640
Therefore, the total cost of wood to make box is Rs. 640.