With an inventory as shown in the table, how many assembly E's should be produced or purchased to produce 15 product X's with this product structure tree? $$\begin{array} { | l | c | c | c | c | c | c | }
\text { Item } & \mathrm { X } & \mathrm { A } & \mathrm { B } & \mathrm { C } & \mathrm { D } & \mathrm { E } \
\hline \text { Inventory } & 5 & 15 & 20 & 8 & 6 & 17 \
\hline
\end{array}$$

Question

With an inventory as shown in the table, how many assembly E's should be produced or purchased to produce 15 product X's with this product structure tree?  $$\begin{array} { | l | c | c | c | c | c | c | } 
\text { Item } & \mathrm { X } & \mathrm { A } & \mathrm { B } & \mathrm { C } & \mathrm { D } & \mathrm { E } \
\hline \text { Inventory } & 5 & 15 & 20 & 8 & 6 & 17 \
\hline
\end{array}$$

Quizplus · Accepted Answer

Looking at the product structure tree, we can see that each X requires 3 A's, 2 B's, and 1 E. Therefore, to produce 15 X's, we would need:
(3A)(15X) = 45A
(2B)(15X) = 30B
(1E)(15X) = 15E

From the inventory table, we can see that we already have 15 A's and 20 B's, so we don't need to produce or purchase any more of these. However, we only have 17 E's, so we would need to produce or purchase an additional:

(15E needed) - (17E in inventory) = -2E

This means we actually have 2 extra E's in inventory, so we don't need to produce or purchase any more of these either. Therefore, the answer is A) 91 (since we don't need to produce or purchase any more of the A's, B's, or E's required to make the 15 X's).

With an Inventory as Shown in the Table, How Many