Problema Solution
A car driver and a motorcyclist started from the same place and headed for the same distance 480 km away. The car driver set off 1.5 hours later than the motorcyclist but arrived 1.5 hours earlier. If the average speed of the motorcycle was 60 kmph, what was the average speed of the car?
Answer provided by our tutors
let
v1 = the average speed of the car
v2 = 60 kmph the average speed of the motorcycle
d = 480 km the distance that each traveled
The car driver set off 1.5 hours later than the motorcyclist but arrived 1.5 hours earlier:
t = the time of the travel of the car
t + 1.5 + 1.5 = t + 3 the time of the travel of the motorcycle
since distance = speed*time we have time = distance/speed for the time of the motorcycle we have:
t + 3 = d/v2
t + 3 = 480/60
t + 3 = 8 hr
t = 5 hr
the speed = distance/time that is for the car we have:
v1 = d/t
v1 = 480/5
v1 = 96 kmph
the average speed of the car was 96 mph.