Question

The difference between the outside and inside surface of a cylindrical pipe 14 cm long is 44 cm^2. If the pipe is made up of 99 cu cm of metal. Find the outer and inner of the radii

Answer 1

volume =
$\pi \: r ^{2} h$
99 = 22×14r^2/7
9= 2 ×2r^2
(9/4) =r^2
3/2 =r
r(inner) = 1•5cm
surface area(inner) = 2 ×22× 3× 14/7
= 44×6
surface area(outer) = 2×22×14r/7=44×2r
difference between the outside and inside surface = 44×2r - 44×6
44= 44(2r-6)
1 = 2r-6
6 = 2r
r(outer)=3 cm