Question

the outer diameter of a pipe is 1.6 metre and it is 15 metre long find the cost of painting the outer surface of the pipe at the rate of rupees 15 per metre square​

Answer 1

Answer:

Given :

Outer diameter = 1 m

Height = 21 m

To Find : Cost of painting pipe at the cost of rate of ₹5/m².

Solution :

First of all we have to find it's Curved surface area.

Curved surface area of a cylinder = 2πrh = πdh

$\frac{22}{7}$×1×21

22×3=66

= 66 m².

Now ,

Cost of painting 1 m² = 5

Cost of painting 66 m² = 5×66 = 330 .

The cost of painting the pipe is ₹330 .