using the five steps for problem solving to answer.

The volume of a rectangler slab of concrete needs to exceed 72cu ft. If the length is 12 feet and the width is 8feet , how thick does the concrete slab need to be?

Solution:

    Volume = length * width * thickness

                  12 * 8 * thickness > 72

                                  thickness  > 72/96

                                  thickness > 3/4

                                  thickness > 0.75 feet