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Question 1206997: A truck starts from Amsterdam at 10 am and heads for Prague, 875 km away. At the same time, a car leaves Prague and heads for Amsterdam at 100 kph. If the vehicles meet at 3 pm, what is the truck's speed?
Found 3 solutions by Theo, josgarithmetic, ikleyn:
Answer by Theo(13342)   (Show Source):
You can put this solution on YOUR website! the distance between amsterdam and prague is 875 kilometers.
the truck leave amsterdam at 10:00 am.
at the same time, the car leaves prague, heading for amsterdam.
they meet at 3:00 pm.
if they meet at 3:00 pm, then they both must have been traveling for 5 hours.
the care will have been traveling 5 * 100 = 500 kilometers.
this means the truck must have been traveling for 875 - 500 = 375 kilometers.
since the truck was also traveling for 5 yours, then the speed of the truck must have been 375 / 5 = 75 kilometers per hour.
since rate * time = distance, .....
the formula for the truck was R * 5 = 875 - D
the formula for the car was 100 * 5 = D
in the second equation, we solved for D to get D = 500.
in the first equation we solved for 875 - D to get 375.
once we got 875 - D, we could then solve for R to get R = 75.
Answer by josgarithmetic(39623)  (Show Source):
You can put this solution on YOUR website!
SPEEDS TIME DISTANCES, km
TRUCK (Amstrd.to.Prag) 5
CAR (Prag.to.Amstrd.) 100 5 100*5=500
TOTAL CONSUMED 875
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SPEEDS TIME DISTANCES, km
TRUCK (Amstrd.to.Prag) 375/5 5 875-500=375
CAR (Prag.to.Amstrd.) 100 5 100*5=500
TOTAL CONSUMED 875
Speed of the truck,  kph
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----------------------NOT THIS------------------------------------
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When they "meet", time passed was 5 hours and total distance traveled for both was sum of 875+100=975 km, but this sum distance not needed. Both car and truck meet at same place.
TRUCK'S SPEED:
 kilometers per hour
MAJOR MISTAKE, took, "...heads for Amsterdam at 100 kph" as '100 km'.
Answer by ikleyn(52835)  (Show Source):
You can put this solution on YOUR website! .
A truck starts from Amsterdam at 10 am and heads for Prague, 875 km away. At the same time, a car
leaves Prague and heads for Amsterdam at 100 kph. If the vehicles meet at 3 pm, what is the truck's speed?
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Do not consider seriously the " solution " by @josgarithmetic, giving the answer
 kilometers per hour for the truck' speed.
It is TOTALLY WRONG.
Use the solution by @Theo, which is correct.
Ignore the post by @josgrarithmetic, for safety of your mind.
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