Answer:
300
Explanation:
The vertex of quadratic ax^2 +bx+c is on the line x=-b/(2a). This unit cost function defines a parabola opening upward, so its vertex is its minimum. The location of the vertex is ...
x = -(-660)/(2ยท1.1) = 660/2.2 = 300
300 cars must be made to minimize the unit cost.
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Note:
The unit cost at that production level will be $8357.