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kiahaider
Jul 20, 2012, 02:55 AM
Two cars that are 600km far a apart are moving towards each other. Their speeds differ by 6km per hour and the cars are 123km far apart after 4.5 hours. Find speed of each car

teacherjenn4
Jul 20, 2012, 10:54 AM
What have you done so far on this problem?

khaakenajaf
Nov 29, 2012, 10:25 AM
let x and y represents speed of two cars c1 and c2 respectively.
difference in speed of both cars is given by
x-y=6 (eq 1)
using formula
distance=speed * time
implies that speed=distance/time
time=4.5 hours
total distance covered=600 km-123 km=477 km
using variables x and y for speed, since cars are moving towards each other
4.5 hours*(x+y)=477 km
x+y=477/4.5
x+y=106 (eq 2)
adding eq1 and eq2
2x=112
=>x=56 km/hour
put value of x in eq1
56-y=6
y=50 km/hour