Williams Optical Inc. is considering a new lean product cell. The present manufacturing approach produces a product in four separate

steps. The production batch sizes are $45$ units. The process time for each step is as follows:

Process Step $1$

$5$ minutes

Process Step $2$

$8$ minutes

Process Step $3$

$4$ minutes

Process Step $4$

$3$ minutes

The time required to move each batch between steps is $5$ minutes. In addition, the time to move raw materials to Process Step $1$ is

also $5$ minutes, and the time to move completed units from Process Step $4$ to finished goods inventory is $5$ minutes.

The new lean layout will allow the company to reduce the batch sizes from $45$ units to $3$ units. The time required to move each batch

between steps and the inventory locations will be reduced to $2$ minutes. The processing time in each step will stay the same.

Determine the value$-$added, non$-$value$-$added, and total lead times, and the value$-$added ratio under the present and proposed

production approaches. If required, round percentages to one decimal place.