A Division Manufactures the "Futura" Model Microwave Oven

Short Answer

A division manufactures the "Futura" model microwave oven. Given that the daily cost of producing these microwave ovens (in dollars) obeys the rule
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where x stands for the number of units produced, find the level of production that minimizes the daily average cost per unit. Round your answer to the nearest integer.
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__________ units per day