To find the volume of a cylindrical drain pipe, you can use the formula for the volume of a cylinder:
\[ V = \pi r^2 h \]
Where:
- \( V \) is the volume,
- \( r \) is the radius of the cylinder,
- \( h \) is the height of the cylinder,
- \( \pi \) is a constant approximately equal to 3.14.
Given:
- The diameter of the pipe is 3 inches, therefore the radius \( r \) is half of the diameter: \[ r = \frac{3}{2} = 1.5 \text{ inches} \]
- The height \( h \) of the pipe is 12 inches.
Now, we can plug these values into the volume formula:
\[ V = 3.14 \times (1.5)^2 \times 12 \]
Calculating \( (1.5)^2 \):
\[ (1.5)^2 = 2.25 \]
Now substitute back into the equation for volume:
\[ V = 3.14 \times 2.25 \times 12 \]
Calculating \( 3.14 \times 2.25 \):
\[ 3.14 \times 2.25 = 7.065 \]
Now multiply by 12:
\[ V = 7.065 \times 12 = 84.78 \]
Thus, the volume of the cylindrical drain pipe is approximately:
\[ \boxed{84.78} \text{ cubic inches} \]
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