Step 1 :The problem is a constrained optimization problem. We need to find the maximum value of the function \(S(L, M)=M L-L^{2}\) subject to the constraint \(M+L=125\).
Step 2 :To solve this problem, we can substitute \(M\) from the constraint into the function \(S(L, M)\), and then find the derivative of the resulting function with respect to \(L\).
Step 3 :Setting the derivative equal to zero will give us the value of \(L\) that maximizes the function.
Step 4 :We can then substitute this value of \(L\) back into the function to find the maximum value.
Step 5 :Let's start by substituting \(M\) from the constraint into the function \(S(L, M)\). We get \(S = -L^{2} + L*(125 - L)\).
Step 6 :Next, we find the derivative of \(S\) with respect to \(L\). We get \(S' = 125 - 4*L\).
Step 7 :Setting the derivative equal to zero, we get \(L_{max} = \frac{125}{4}\).
Step 8 :Substituting this value of \(L_{max}\) back into the function, we get \(S_{max} = \frac{15625}{8}\).
Step 9 :Final Answer: The maximum value of the sales is \(\boxed{\$1953.13}\).