Question 1033491
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The daily production costs C( in dollars per unit) for a manufacturer of lighting fixtures are given 
by the quadratic function C(X)=800-10X+0.25X2 where x is the number of units produced. How many fixtures should be produced 
to yield a minimum cost per unit?
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Use the formula for the vertex of a parabola x = {{{-b/2a}}}.


In your case b = -10, a = 0.25.


Hence, X = {{{-((-10)/0.25)}}} = {{{10/0.25}}} = 40.