# Min-Max problem

#### Yankel

##### Active member
Hello,

I need some help with this question, it is not very clear and I find it hard to translate from text to math...

Good work!

#### HallsofIvy

##### Well-known member
MHB Math Helper
MarkFL also asked "How can you do this without calculus?"

In this problem the profit function is -x2+ 980x- 3000, a quadratic function. Its graph is a parabola opening downward and so it maximum value is at its vertex. And you can find that by completing the square.