Working alone, Ryan can dig a 10 ft by 10 ft hole in five hours. Castel can dig the same hole in six hours. How long will it take them if they worked together?
. Rates: Ryan: 1 hole per 5 hours Castel: 1 hole per 6 hours . Let x = time if working together then x(1/5 + 1/6) = 1 x(6 + 5) = 30 11x = 30 x = 30/11 x = 2.7273 hours or x = 2 hours and 44 minutes
