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costing stuff has been a major problem for us. First Mammoth was not profitable and now
Maximum.
“Looking at the ABC analysis, I see two problems. First, we do many more activities than the
ones you have listed. If you had included all activities, maybe your conclusions would be
different. Second, you used number of setups and number of inspections as allocation bases. The
numbers would be different had you used setup-hours and inspection-hours instead. I know that
measurement problems precluded you from using these other cost-allocation bases, but I believe
you ought to make some adjustments to our current numbers to compensate for these issues. I
know you can do better. We can’t afford to phase out either product.”
Jacobs knows that his numbers are fairly accurate. As a quick check, he calculates the
profitability of Maximum and Mammoth using more and different allocation bases. The set of
activities and activity rates he had used results in numbers that closely approximate those based
on more detailed analyses. He is confident that headquarters, knowing that Maximum was
introduced only recently, will not ask Plum to phase it out. He is also aware that a sizable portion
of Clark’s bonus is based on division revenues.
Phasing out either product would adversely affect his bonus. Still, he feels some pressure from
Clark to do something.
Required:
1. Using activity-based costing, calculate the gross margin per unit of the Maximum and
Mammoth models.
2. Explain briefly why these numbers differ from the gross margin per unit of the Maximum
and Mammoth models calculated using Plum’s existing simple costing system.
3. Comment on Clark’s concerns about the accuracy and limitations of ABC.
4. How might Plum find the ABC information helpful in managing its business?
5. What should Steve Jacobs do in response to Clark’s comments?
SOLUTION