The Cost C in Dollars of Operating a Machine Is $C ( n ) = 4.8 n ^ { 2 } - 192 n + 426$

Short Answer

The cost C in dollars of operating a machine is related to the number of minutes n the machine is run by the function $C ( n ) = 4.8 n ^ { 2 } - 192 n + 426$ . For what number of minutes is the cost of running the machine a minimum?