Okay, here we have this:
Considering the provided information, and the given function we are going to calculate R(300) and then we will interpret the result, so we obtain the following:
[tex]\begin{gathered} R(x)=17x \\ R(300)=17\cdot300 \\ R(300)=5100 \end{gathered}[/tex]Considering that x corresponds to the number of hats sold, then it means that if 300 hats are sold, the total revenue will be equal to $5100.