A bus travels 200 km at a constant speed. A car travelling 10 km/h faster than the bus, completes the same distance in 1 hour less than the bus.
4.1 How many hours does the bus take to travel the 200 km?
4.2 What is the speed of the car?
Let the speed of bus = b km/hr
then speed of car = (b + 10) km/hr
time taken by bus for 200 km = 200/b hr
time taken by car for 200 km = 200/(b+10) hr
200/b â€" 1 = 200/(b +10)
200b + 2000 â€" b² â€" 10b = 200b
b² + 10b â€" 2000 = 0
(b + 50)(b â€" 40) = 0
b = â€" 50 or b = 40
speed of bus = 40 kmph
time for 200 km = 200/40 = 5 hr
speed of car = 40 + 10 = 50 kmph
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