[tex]\text{To make this question easier, lets find how much she makes in 1 hour}\\\\\text{We know that she makes 27 dollars in 3 hours, so divide 27 by 3}\\\\27\div3=9\\\\\text{Now we know that she makes \$9 an hour, we can find how much}\\\text{she makes in 4 hours:}\\\\9\cdot4=36\\\\\boxed{\$36}[/tex]