Hi
Let x and ( x-2hr) represent the times that Sam and Allen traveled respectively
Question states*** D = r*t (distances being the same for both
45mph*x = 55mph(x-2)
Solving for x
110 = 10x
11hr = x, time Sam traveled. Allen traveled 9 hrs.
CHECKING our Answer***
45mph*11hr = 55mph*9hr = 495mi