It is given that diameter of the (oil drum) cylinder = 2 m.
Radius of cylinder = \(\frac{d}{2}=\frac{2}{2}\) = 1 m.
Total surface area of a cylindrical drum
= 2πr(r + h)
= 2 × \(\frac{22}{7}\) × 1(1 + 7)
= 2 × \(\frac{22}{7}\) × 8 = \(\frac{352}{7}\)m2 = 50.28 m2 .
So, the total surface area of a drum = 50.28 m2
Painting charge per 1 m2 = ₹ 5.
Cost of painting of 10 drums
= 50.28 × 5 × 10
= ₹ 2514