<PRE><B>Question 153052</B>
If a bike shop determines that when x hundred bikes are built, the average cost per bike is given by c(x)=0.6^2-0.8x+5.854 where c(x) is in hundreds dollars. How many bikes should be built to mininize the average cost per bike. 
c(x)=0.6x^2-0.8x+5.854
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Cost is a quadratic with a = 0.6, b = -0.8
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Minimum cost occurs when x = -b/2a = 0.8/(2*0.6) = 0.2/0.3 = 0.6667
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# of bikes should be 0.667*100 = 66 or 67

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Cheers,
Stan H.</PRE>