A contractor decided to build homes that will include the middle 80% of the market. If the average size of homes built is 1810 ft2 with a standard deviation of 92 ft2, find the maximum and minimum sizes of the homes the contractor should build. Assume that the size of homes is normally distributed.

The physical fitness of an athlete is often measured by how much oxygen the athlete takes in (which is recorded in milliliters per kilogram, ml/kg). the mean maximum oxygen uptake for elite athletes has been found to be 60 with a standard deviation of 7.2. assume that the distribution is approximately normal.

Four quarts of a latex enamel paint will cover about 200 square feet of wall surface. how many quarts are needed to cover 98 square feet of kitchen wall and 52 square feet of bathroom wall

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.