Use this scenario for the following question(s).
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 7.5 productive hours available in a day and the manufacturer wishes to produce 400 units. Balance the line by assigning tasks to workstations to fill up as much takt time as possible. Break ties by assigning the longest task first.
$$\begin{array} { | c | c | c | }
\hline \text { Task } & \text { Time } ( \mathrm { sec } ) & \text { Predecessor } \
\hline \text { A } & 45 & \cdots \
\hline \text { B } & 50 & \text { A } \
\hline \text { C } & 20 & \text { A } \
\hline \text { D } & 55 & \text { A } \
\hline \text { E } & 15 & \text { D } \
\hline \text { F } & 65 & \text { D } \
\hline \text { G } & 25 & \text { E } \
\hline \text { H } & 35 & \text { B, C, F, G } \
\hline
\end{array}$$
-Refer to the scenario above. How many workstations must be added to increase the output rate to one unit per minute?
A)1
B)2
C)3
D)4

Question

Use this scenario for the following question(s).
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 7.5 productive hours available in a day and the manufacturer wishes to produce 400 units. Balance the line by assigning tasks to workstations to fill up as much takt time as possible. Break ties by assigning the longest task first.
 $$\begin{array} { | c | c | c | } 
\hline \text { Task } & \text { Time } ( \mathrm { sec } ) & \text { Predecessor } \
\hline \text { A } & 45 & \cdots \
\hline \text { B } & 50 & \text { A } \
\hline \text { C } & 20 & \text { A } \
\hline \text { D } & 55 & \text { A } \
\hline \text { E } & 15 & \text { D } \
\hline \text { F } & 65 & \text { D } \
\hline \text { G } & 25 & \text { E } \
\hline \text { H } & 35 & \text { B, C, F, G } \
\hline
\end{array}$$
-Refer to the scenario above. How many workstations must be added to increase the output rate to one unit per minute?
A)1
B)2
C)3
D)4

Quizplus · Accepted Answer

To calculate the output rate, we need to first calculate the cycle time or takt time:

$$ 	ext{Cycle time} = \frac{	ext{Available production time}}{	ext{Required daily units}} = \frac{7.5 	ext{ hours} 	imes 3600 	ext{ sec/hour}}{400 	ext{ units}} = 67.5 	ext{ sec/unit}$$

From the table, we can assign tasks to different workstations to create a balanced line with the longest task assigned first in case of a tie:

| Workstation 1 | Workstation 2 | Workstation 3 | Workstation 4 |
|---------------|---------------|---------------|---------------|
| D             | F             | A             | B             |
| E             | H             | C             |               |
| G             |               |               |               |

We can see that there are four workstations required to produce one unit per minute, so the answer is (C) 3.

Use This Scenario for the Following Question(s) -Refer to the Scenario Above