Question

A 5 foot-long cylindrical pipe has an inner diameter of 6 feet and an outer diameter of 8 feet.
If the total surface area is kn(n=Pi) ,what is the value of k ?

Answer 1

Area = 2.pi.r.h + 2.pi.R. h + 2[ pi(R^2 - r^2)]
= 2.pi.5 (3 + 4) + 2[pi (4^2 - 3^2)]
= pi.70 + 2.pi.7
= 84.pi
so k = 84

Answer 2

ty