Question

At what speed would Mack have to drive to complete 550 miles in 12 hours if he takes a 20-minute rest break after 3 hours of driving.

Answer 1

12/3 is 4 breaks 12x60 is 720mins at most with 4x20= 80 = 720-80=640/ 60 means we have 10.67 hours left 550/10.67= 51.55 mph