Answer: Ben earn $6 per hour.
Step-by-step explanation: Given that Ben has a part time job at the fun station. He worked 13.5 hours last week and $81.
We are to find the earning of Ben per hour.
We will be using the UNITARY method to solve the problem.
We have
Earning of Ben in 13.5 hours = $81.
Therefore, the earning of Ben in 1 hour is given by
![\$(81)/(13.5)=\$6.](https://img.qammunity.org/2019/formulas/mathematics/high-school/e2e5k7d48lx0nm9w9rvce3vs02eclf6ux3.png)
Thus, Ben earn $6 per hour.