Math
I have a homework
A manufacturer produces bolts of a fabric with a fixed width. A quantity q of this fabric (measured in yards) that is sold is a function of the selling price p (in dollars per yard), so we can write q=f(p). Then, the total revenue earned with selling price p is R(p)=pf(p).
Find R′(30), given f(30)=12000, and f′(30)=−450. (What does this mean?)
R′(30)=?
R′(30)=