The cost of cellophane paper is ₹ 40 per kg. How much expenditure would be there to cover a cube of edge 25 cm with a cellophane paper, if one kg of paper covers 50 sq.cm. area?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → ₹ 3000
The paper has to cover the whole surface of the cube, which is made of 6 equal square faces.
Surface area \(=6\times25^{2}=6\times625=3750\) sq. cm
Paper needed \(\displaystyle =\frac{3750}{50}=75\) kg (one kg covers 50 sq. cm)
Cost \(=75\times40=\) ₹ 3000