How do you calculate the sq ft of a round pipe 40' x 12"?

Question

How do you calculate the sq ft of a round pipe 40' x 12"?

Answer 1

surface area? including the inside? Need the ID or thickness to get the inside area.

IF 12" is the diameter, then outside area (only) is

A = π(12)(40*12) in² = 18100 in² = 126 ft²

Answer 2

The Circumference of the pipe will be π x Diameter.

3.142 x 1foot (if the 12" is the diameter). = 3.142ft.

Imagine the pipe cut lengthwise and opened up to a flat plate.

It will be 40' long and 3.142' wide.

40' x 3.142' = 125.7 ft².

Answer 3

I guess they mean if you cut the pipe in half lengthwise and flattened it. Then it would be flat and be rectangular. The diameter is 12 inches (one foot). You need the circumference of the pipe. That would be (3.14x1=3.14 feet). Pi times the diameter. On the split flattened pipe that would be the dimension of one side. The other side is the length of the pipe. So the sq ft of the pipe would be: 3.14 x 40=125.66 square feet.

Answer 4

No, you can't figure square feet in something that is round.