成管會損益兩瓶平 - 會計

Megredy Company prepared the following absorption-costing income statement
for the year ended May 31, 20x5


Sales(16,000units) $320,000
Cost of goods sold(including $6250 production-volume
variance) 222,250
---------
Gross margin $97,750
Selling and administrative expenses 46,000
----------
Operationg income $51,750

Additional information follows:
Selling and administrative expenses include $1.50 of variable cost per unit
sold. There was no beginning inventory, and 17,500 units were produced.
Variable manufacturing costs were $11 per unit. Actual fixed costs were equal
to budget fixed costs.

Required:Caculate the break-even units

解答給的是: ($2.5x20,000+$22,000)/(20-11-1.5)=9,600

但我看到題目,第一個想法是用歸納成本法來算BEP:

[($2.5x20,000+$22,000)-(17,500-16,000)x$2.5]/(20-11-1.5)=9,100

請問為什麼不是用歸納成本法來算呢?
因為題目也沒有說明要使用哪一種>"<

再次感謝回答~~

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