>>13226905intuitively, I would say Alice and Bob are the most productive workers, and they should tell Charlie to relax, so the three of them would take 2 hours to complete the job
mathematically:
Alice can do half the job in 30m, Bob in 90m and Charlie in 150m.
Alice can do the entire job in 60m, Bob in 180m and Charlie in 300m
R.: if they want to do the job as fast as possible Bob and Charlie should relax and let Alice finish it in 1 hour. if they want to divide it equally by the three of them, it will be A = 20m + B = 30m + C = 75m = 125m, 2h and 5m
of course this assumes there's only one keyboard and only one person can work at a given moment.
