Juan accepted a job to roof a new house. He calculated that he can complete the job in 20 hours. He hired a trainee to assist him. He has seen the trainee work and estimates
that the trainee working alone would take 25 hours to complete the job. How much time
should the two of them working together need to roof the house? (Round your answer to
the nearest tenth.)
hours
Type the correct answer in decimal form, then
press Enter.