A certain electronics manufacturer found that the average cost $\displaystyle {C}$ to produce x DVD/Blu- ray players can be found using the equation $\displaystyle {C}={0.03}{x}^{{2}}-{5}{x}+{900}$. What is the minimum average cost per machine and how many DVD/Blu-ray players should be built in order to acheive that minimum?

The minimum average cost is

The number of DVD/Blu-ray players that should be build to acheive the minimum is

**Answer both to the nearest whole number.