Cost function math problem?

How did they get problem 2 a) c) e)





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Cost function math problem?
a) since it says the relationship of cost to number produced is linear, you are solving for the equation of a line. They give you two points:





(100, 2200) and (300, 4800). Now use whatever method you want to get the equation. Personally I almost always use y=mx+b.





m = (4800-2200) / (300-100) = 13


y=13x+b





Now plug in one of the points for x and y and solve for b:





2200 = 13(100) + b


2200=1300+b


900 = b





y = 13x + 900





c) The y intercept is the value of y when x = 0. So take the equation and plug in x=0:


y = 13(0) + 900 = 900.





e) You were right on this one... P(q) = R(q) - C(q). You just need to plug in the R(q) from part (d) and the C(q) from part (a)...





P(q) = 17.5q - (13q + 900)





Best of luck!