Question

7.
The inner diameter of a circular well is 3.5 m. It is 10 m deep. Find
its inner curved surface area,
(ü) the cost of plastering this curved surface at the rate of 40 per m².
om there is a cylindrical pipe of length 28 mand diameter​

Answer 1

Step-by-step explanation:

hope it helps. i

its inner diameter is 110 m square

cost of plasting is rs. 4,400

Answer 2

Answer: hope it helps you

Step-by-step explanation:

inner diameter of well =3.5m

Inner radius of well (r)=  

2

3.5

​  

m

Height of well (h)=10m

Therefore,

Inner curved surface area of well  

=2πrh

=2×  

7

22

​  

×  

2

3.5

​  

 times10

=110m  

2

 

Now,

Cost of plastering =Rs.40 per square meter

Therefore,

Cost of plastering this well =40×110=Rs.4400