Answer
4 hours
Work Step by Step
Total distance is 300mi
Total time is 5.5 hours
Distance traveled by bus: d
Time=$\frac{distance}{speed}$
total time (t) = time by bus ($t_{b}$) + time by train ($t_{t}$)
t=$t_{b}$+$t_{t}$
t=$\frac{d}{40}$+$\frac{300-d}{60}$
multipy by 120
660=3d+2(300-d)
660=3d+600-2d
60=d
$t_{t}$=$\frac{300-d}{60}$=$\frac{240}{60}$=4h
