Emma can run all-around two arenas in 20 hours. If it takes Fernando twice as long to run his course, what's the total time it takes both of them to run all around the two arenas?
Thoughts? Step-by-step reasoning:
If it takes Emma 20 hours to run all around the two arenas, it takes Fernando 2 * 20 = 40 hours to run the same distance. Together, they take a total of 40 + 20 = 60 hours to run all around the arenas.
Thus, the answer is 60.