Here is the question:
I have posted a link there to this thread so the OP can view my work.Calculus - Trapezoidal Rule - Cross Sections - Pools?
A circular swimming pool has diameter 28 feet. The depth of the water changes slowly from 3 feet at a point A on one side of the pool to 9 feet at a point B diametrically opposite A. Depth readings h(x) (in feet) taken along the diameter AB are given in the following table, where x is the distance (in feet) from A.
Use the trapezoidal rule, with n=7, to estimate the volume of water in the pool. Approximate the number of gallons of water contained in the pool (1 gal= approx. 0.134 ft^2)
I can't understand how the trapezoidal rule can approximate a three dimensional figure.
Anyone have any ideas?