Answer:
7.5 hours
Step-by-step explanation:
Time is inversely proportional to speed for the same distance. The bus speed is 40/50 = 4/5 of the car speed, so it will take 5/4 as long.
(5/4)·(6 h) = 7.5 h
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If you like, you can use the relations ...
distance = speed × time
time = distance/speed
to compute the distance between A and B, then the time at the lower speed:
distance = (6 h) × (50 mi/h) = 300 mi
time = (300 mi)/(40 mi/h) = 30/4 h = 7.5 h
