SOLUTION: A car starts with the speed 60 km/hr from prayad at 3 p.m. After 1 hour a second car starts with the speed 80 km/hr on the same track to cross to the first car. After how many kms

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Question 567271: A car starts with the speed 60 km/hr from prayad at 3 p.m. After 1 hour a second car starts with the speed 80 km/hr on the same track to cross to the first car. After how many kms the second car wil meet the first?
Found 2 solutions by mananth, josmiceli:
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!

Car A speed = 60 km/h
Car B speed = 80 km/h
when car B starts Car A has traveled 60 km
Let the distance they meet be x km
they are going in the same direction
subtract their speeds 80-60=20 km/h
Time taken by car A = time taken by Car B
(x-60)/60 = x/80
80(x-60)=60x
80x-480=60x
80x-60x= 480
20x=480
/20
x= 24 km

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The 1st car gets a head start of +1+ hr
In +1+ hr, it travels +60%2A1+=+60+ km
Count time when the 2nd car leaves.
Let +t+ = time in hours until they meet
Let +d+ = distance 2nd car travels until they meet
-----------------
Equation for 2nd car:
+d+=+80t+
Equation for 1st car:
+d+-+60+=+60t+
--------------
By substitution:
+80t+-+60+=+60t+
+20t+=+60+
+t+=+3+
--------------
+d+=+80t+
+d+=+80%2A3+
+d+=+240+
When both cars have traveled 240 km,
they will meet