Question

the outer diameter of a pipe is 70 cm and has a length of 21 m .find the cost of polising its outer surface at the rate of rupees 10 per square m.(hind for it is 2pai radius into hight)​

Answer 1

Answer:

Step-by-step explanation:

Write down all the given points:

Diameter= 70cm= 0.7m

Hence radius= 70/2= 35cm = 0.35m

Lenght(height) = 21m

First we have find the curved surface area which is

CSA= $2\pi rh$

= $2*\frac{22}{7}*0.35*21$

=46.2 square m.

Now to find the total cost

Amount to polish 1 square m.= Rs. 10

Amount to polish 46.2 square m.= 46.2*10

=Rs. 462