Question

Hi friends

50 closed cylindrical cisterns with radius 4 cm and height 10 cm are to be produced. How many cm sq. of tin-sheet will be required to produce them? Find the cost of tin-sheet required at the rate of ₹220 per m sq. .

Answer 1

This is a question on Surface area :

Surface area of a cylinder :

SA = 2πr² + 2πrh

SA of one cylinder :

SA = 2 × 3.142 × 4² + 2 × 3.142 × 4 × 10

= 351.904 cm²

We have 50 cylinders.

The total area required is thus :

50 × 351.904  = 17595.20 cm²

Convert this to m²

1 m² = 10000cm²

17595.20 / 10000 = 1.759520 m²

Cost:

1.759520 × 220 = 387.0944

= Rs 387.0944