Compare the areas of two rectangular cross sections of an air-conditioning duct along a length of the duct that shrinks in width from 20 inches to 12 inches and in height from 8 inches to 6 inches. Find the difference of the areas, and determine the percentage that each cross section is of the other. Then, name the solid figure from which the two rectangular cross sections are formed.

Calculate the area of the larger cross section.

Calculate the area of the smaller cross section.

Find the difference of the cross section areas.

Calculate the percentage that the smaller area is of the larger area.

Calculate the percentage that the larger area is of the smaller area.

Determine the solid figure from which the cross sections are formed.

This applet is provided by Walch Education as supplemental material for their mathematics programs. Visit www.walch.com for more information.