A pool in the shape of a circle measures 10 feet across. One cubic yard of concrete is to be used to create a circular border of uniform width around the pool. If the border is to have a depth of 4 inches, how WIDE will the border be?

NOTE: 1 cubic yard = 27 cubic feet.

I believe we use a volume formula here, right?

Aslo, what is meant by the math phrase "uniform width"? I always see uniform width in geometry books.