Question

a metal pipe is 70 cm long. the inner diameter of a cross section is 4 cm and the outer diameter is 4.8 cm. find inner surface area, outer surface area , total surface area

Answer 1

inner c.s.a of pipe =2pier
=2*22/7*2
=88/7=12.4...
outer c. S. a =2pierl =2*22/7*2.4
=44* .8=35.2
tsa =2pie r(h+r)
put the values you will get the answer but r will be 4.4 by adding inner r and outerR

Answer 2

inner surface area:-880cm^2
outer surface area:-1056cm^2