A lead pipe 20 ft long is 3/8 inch thick and has an inner diameter of 3 inches. Find the volume of l

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A lead pipe 20 ft long is 3/8 inch thick and has an inner diameter of 3 inches. Find the volume of lead in it.

A lead pipe is a cylinder. We want the volume of a cylinder.

Convert 20ft to inches:
20ft = 12(20) = 240 inches

Find the inner radius:
1/2 * inner diameter
1/2 * 3 = 3/2

Now add the thickness for the total radius
3/2 + 3/8 = 12/8 + 3/8 = 15/8

Find volume of the lead where volume = pi r^2 h
Lead vol (V) = Overall volume - inner volume
Lead Vol = pi(15/8)^2(240) - pi(3/2)^2(240)
Lead Vol = 240pi(225/64 - 9/4)

9/4 = 144/64
Lead Vol = 240pi(225/64 - 144/64)
Lead Vol = 240pi(81/64)
Lead Vol = 303.75pi