ABC Inc. has introduced a process improvement that increases output with less materials cost. Under the old process, the output is 600 units per hour. The labor cost is $30 per hour with 5 workers per hour. The material input is $10 /unit for each of the 600 units. Under the new process, the output is 750 units per hour. The material input is \$8/unit for each of the 750 units. The labor cost is the same. Overhead is charged at 1.5 times direct labor cost in both processes. What increase in productivity is associated with the process improvement