Question: how do i calculate how much paint i need for a pipe?
Answer: Pipe Dia in mm (D) = 10″ X 25.4 = 254mm.
Length of Pipe (L) = 100 meters = 100000 mm.
Surface area of pipe for one meter (A) = Pi X D = 3.141 X 254 = 0.797814 Sq. ... 
Total Surface Area = A X L = 797.814 X 10000 0= 79781400 Sq.MM.