Solve the problem.
-BJ can overhaul a boatʹs diesel inboard engine in 15 hours. His apprentice takes 30 hours to do the samejob. How long would it take them working together assuming no gain or loss in efficiency?
A)10 hr
B)4 hr
C)45 hr
D)6 hr

Question

Quizplus · Accepted Answer

Working together, BJ and his apprentice can complete $\frac{1}{15} + \frac{1}{30} = \frac{2}{30} + \frac{1}{30} = \frac{3}{30} = \frac{1}{10}$ of the job per hour, meaning it would take them 10 hours to complete the job together.

Solve the Problem. -BJ Can Overhaul a Boatʹs Diesel Inboard Engine in 15