Utility Suppose your newspaper is trying to decide between two competing desktop publishing software packages, Macro Publish and Turbo Publish. You estimate that if you purchase x copies of Macro Publish and y copies of Turbo Publish, your company's daily productivity will be

U(x, y) = 6x ^0.8 y ^0.2 + x,

where U(x, y) is measured in pages per day (U is called a utility function). If x = y = 10, calculate the effect of increasing x by one unit, and interpret the result.