Question

Johnson Canniver has a repair shop. He bought a used lawn mower for $35.00 from a customer. He spent $39.17 on parts to repair the mower. He also painted and polished the mower at a cost of $36.43. He was able to sell the refurbished lawn mower for $155.00. If it took 4.5 hours to do all the work, how much did he earn per hour to the nearest cent? (Hint: Find the markup on the lawn mower first.)