Problem $6-21($Algo$)$

Consider the following tasks, times, and predecessors for an assembly of set$-$top cable converter boxes:

TASK ELEMENT TIME $($MINUTES$)$ PRECEDING TASKS

A $6$

B $6$ A

C $7$ B

D $6$ B

E $8$ C$,$ D

F $6$ A

G $6$ F

H $7$ G

I $6$ E$,$ H

Given a cycle time of $19$ minutes, develop two alternative layouts. Use the longest task time rule and the largest number of following tasks as a secondary criterion. What is the highest efficiency of your layout, assuming the $19-$minute cycle time?

Note: Enter your answer as a percentage rounded to $2$ decimal places.