A cubical wooden box of internal edge 1 m is made of 5 cm thick wood. The box is open at the top. If the wood costs ₹9600 per cubic metre, find the cost of the wood required to make the box.

Given,

Internal edge of cubical wooden box = 1 m

Thickness of wood = 5 cm = 0.05 m

We know that,

External length = (1 + 0.05 × 2) = 1.1 m

Breadth = (1 + 0.05 × 2) = 1.1 m

Height = (1 + 0.05) = 1.05 m

By formula,

Volume of the wood used = Outer volume – Inner volume

Substituting the values we get,

Volume of the wood used = 1.1 × 1.1 × 1.05 – 1 × 1 × 1

= 1.2705 – 1

= 0.2705 m³

Cost of 1 m² of wood = ₹9600

So, the cost of 0.2705 m² of wood = ₹9600 × 0.2705

= ₹2596.80.

Hence, cost of wood required to make the box = ₹2596.80