John was gifted a new Hayabusa. He drove x miles at 55mph. Then he drove x+20 miles at 40mps. He drove his bike for 100 minutes. How much distance did he travel?
t1 + t2 = 100 minutes = 100/60 hours
t1 = x/55
t2 = (x+20)/40
x/55 + (x+20)/40 = 100/60
x = 1540/57
Thus, Total distance = x + (x+20) = 4220/57 miles = 74 2/57 miles