In this problem the store sold 530 dollars so this correspound to the 100 so we can calculate the 6% to know how much she make so we use a rule of three:
[tex]\begin{gathered} 530\to100 \\ x\to6 \end{gathered}[/tex]and the equation will be:
[tex]\begin{gathered} x=\frac{530\cdot6}{100} \\ x=31.8 \end{gathered}[/tex]So she earned $31.80 dollars in commission
and the store will made:
[tex]530-31.8=498.20[/tex]