Question 414335: Thanks for your help.
Shouldn't the 500 meters be converted to .5km and the 1000 meters be converted to 1km.
Same as converting 26400ft. to miles, to get mph. 26400ft./5280ft. = 5 miles.
My calculation would be (.5km + 1km / 180km/h) x 60 mins. = .5 minutes.
Which equals 30 seconds.
Question 1157: Two trains, one 500 meters long and the other 1000 meters long, are traveling in opposite directions on parallel tracks. The first train is traveling at 100km/h and the other at 80km/h. How long will it take for the trains to pass each other from the moment the locomotives are at the same point?
Answer by khwang(438) (Show Source):
You can put this solution on YOUR website!
The diagram as below.
500 m 100 km/h ->
A<------>B (1st train)
C<------------->D (2nd train)
<- 80 km/h 1000 m
When they pass each other after t hrs,diagram as
A B
<------>
<------------->
C D
After t hrs, B moves 100 t km and C moves 80 t km.
So we have 100 t + 80 t = BC = CD + AB = 1000+ 500
So, 180 t = 1500, t = 25/3 hrs
[Or get t by (1000+ 500)/(100+80) directly.
Answer: it takes 25/3 hrs for the trains to pass each other
from the moment the locomotives are at the same point.
Or get t by (1000 + 500)/ (1000+ 60) directly.
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! The total length is 1.5 km
The relative speed is 180 km/hr = 3 km/minute
1.5/3 = 0.5 minutes
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You're right, the units have to match.
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