Answer: The level of production is 4 units and the corresponding price that maximize the profits is $121.
Step-by-step explanation:
Since we have given that
the demand for steel would be
[tex]p=201-20x[/tex]
[tex]R(x)=xp(x)=x(201-20x)=201x-20x^2[/tex]
Total cost of producing x units of steel would be
[tex]C(x)=153+41x[/tex]
Profit = R(x)-C(x)
So, it becomes,
[tex]profit=201x-20x^2-153-41x\\\\P(x)=-20x^2+160x-153[/tex]
First we derivative w.r.t to x we get that
[tex]P'(x)=-40x+160[/tex]
Now, we will find the critical points,
[tex]-40x+160=0\\\\-40x=-160\\\\x=\dfrac{-160}{-40}\\\\x=4[/tex]
So, now second derivative w.r.t. x.
We get that
[tex]P''(x)=-40<0[/tex]
So, there will be maximum profit at 4 units of level of production and the corresponding price that maximize the profit would be
[tex]p(x)=201-20x\\\\p(4)=201-20(4)\\\\p(4)=201-80\\\\p(4)=121[/tex]
Hence, the level of production is 4 units and the corresponding price that maximize the profits is $121.