Question

The diameter of a cylindrical construction pipe is 4 ft, and its

length is 18 ft.
Answer the parts below.

Answer 1

• 72π ft³
• 226.19 ft³

Explanation:

(a) The figure shows the diameter of the pipe is 4 ft, so its radius is 2 ft. The equation for the volume of a cylinder is ...

V = πr^2·h

Filling in r=2 and h=18, we have ...

V = π(2 ft)^2(18 ft) = 72π ft^3

The exact volume is 72π ft³.

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(b) Using a sufficiently accurate value of pi, the numerical value of the volume is ...

72π ft^3 ≈ 226.19 ft^3

The approximate volume is 226.19 ft³.