A metal pipe is 77 cm long. The inner diameter of a cross section is 4 cm, the outer diameter being 4.4 cm.  Find its (i) inner curved surface area,(ii) outer curved surface area,(iii) total surface area

Explanation

1) Inner surface area=`2pirh`

`=2*22/7*77*2`

=968`cm^2`

2) Outer surfacce area=`2pirh`

`=2*22/7*2.2*77`

=10647.8`cm^2`

3) Total surface area=outer surface area+inner surface area+ring.

=968+1064.8+`pi(R^2+r^2)`

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