$122,500
1) Since the revenue is given by this product: price x quantity, we can write it out and plug into that the given data:
![\begin{gathered} R=P\cdot Q \\ R=(30+x)(4000-100x) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/eqs1v8myfzipxyiod7g06gwhwoif625bgb.png)
2) Now, let's expand those factors:
![\begin{gathered} R=(30+x)(4000-100x) \\ R=120,000-3000x+4000x-100x^2 \\ R=-100x^2+1000x+120,000 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/gr30f4bbjnvmj7umj1jtel53sf7jdqrryz.png)
The maximum total revenue is given by the y-coordinate on the Vertex of that parabola. Let's use another formula for that:
![Y_V=-(\Delta)/(4a)=(-(1000^2-4(-100)(120000)))/(4(-100))=122500](https://img.qammunity.org/2023/formulas/mathematics/college/olqncdrhi7c1oo7h21vcyxzmtl27jhgpqm.png)
3) Hence, the maximum revenue would be $122,500