How many gallons of water in a 3 inch pipe 10 feet long?

Answer 1

Assume the "3 inch" is the pipe's inside diameter.

Capacity = (pi x R2 x L) = (pi x 1.52 x 120) cubic inches.

1 gallon = 231 cubic inches.

Gallons capacity = (pi x 2.25 x 120 / 231) = 3.672 gallons (rounded)

That's the capacity of the pipe. We have no way of knowing how much water is in it.
We only know that it's no more than 3.672 gallons.

Answer 2

A 3-inch pipe has a diameter of 3 inches, which corresponds to a radius of 1.5 inches (3 divided by 2). The volume of water that can fit in the pipe can be calculated using the formula for the volume of a cylinder: V = πr^2h, where r is the radius and h is the height. Converting the measurements to consistent units (inches), the volume of water in the pipe would be approximately 1.321 gallons.

Answer 3

12.2 US gallons.