The Process Design Team at a Manufacturer Has Broken an Assembly

The process design team at a manufacturer has broken an assembly process into eight basic steps, each with a required time and predecessor as shown in the table. There are 8 productive hours available in a day and the manufacturer wishes to produce 400 units using seven workers-one for each station.
$$\begin{array} { | c | c | c | } \hline \text { Task } & \text { Time } ( \mathrm { sec } ) & \text { Predecessor } \\\hline \mathrm { J } & 45 & \cdots \\\hline \text { K } & 50 & \mathrm {~J} \\\hline \text { L } & 40 & \mathrm {~J} \\\hline \text { M } & 55 & \mathrm {~K} , \mathrm {~L} \\\hline \mathrm { N } & 40 & \mathrm { M } \\\hline \text { O } & 65 & \mathrm { M } \\\hline \text { P } & 25 & \mathrm {~N} \\\hline \text { R } & 35 & \mathrm { O } , \mathrm { P } \\\hline\end{array}$$ Balance the line according to the longest operation rule and calculate the percent idle time. Using the same arrangement of tasks at work stations, what is the greatest output that can be achieved in an eight-hour day and what is the percent idle time of this design?