Step 1: Make a note of the given information

Diameter of the (oil drum) cylinder = 2 m

Height = 7 m

Painting change per 1 m^2 = 3 rupees

Step 2: Find the total surface area of a cylindrical drum

FORMULA: Total surface area of a cylindrical drum = 2 \pi r (r + h)

= 2 *\pi*1(1 + 7) ( \because diameter = 2m

radius = \frac{2}{2} = 1m = 2 * \frac{22}{7} * 8

= \frac{352}{7}

= 50.28 m^2

Step 3: Calculate the cost of painting of 10 drums

Total surface area of a cylindrical drum = 50.28 m^2

Cost of painting of 10 drums = 50.28 ×3×10

= 1508.40 rupees