Two trains for Lahore leave Rawalpindi at 8:30 AM and 9:00 AM and travel at 60 km/h and 70 km/h. How many kilometers from Rawalpindi will the two trains be together:

A. 100
B. 190
C. 210
D. 150

3 Comments to “Two trains for Lahore leave Rawalpindi at 8:30 AM and 9:00 AM and travel at 60 km/h and 70 km/h. How many kilometers from Rawalpindi will the two trains be together:”

AlI akbar says:

November 23, 2018 at 5:27 pm

What’s formula use for solving this problem

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1. Arif Khan says:
  
  November 24, 2018 at 8:37 am
  
  Explanation This train problem with formula:
  Formula is , STD = (Speed Time and Distance)
  First Train:
  S=60
  T=( 8:30 to 9:00 ) = 30 Minutes
  Now;
  Distance = Speed * Time
  D = 60km/h * 30M / 60h = 30km/h
  We have First train Speed of first 30 Minutes is 30km/h Now make it Simple:
  Adding 60km/h to First Train Speed and 70km/h to Second Train Speed
  At 9:00 AM
  First Train: (30km/h) | Second Train: ( 0km/h)
  At 10:00 AM
  First Train: (90km/h) | Second Train: ( 70km/h)
  At 11:00 AM
  First Train: (150km/h) | Second Train: ( 140km/h)
  At 12:00 PM
  First Train: (210km/h) | Second Train: ( 210km/h)
  
  So at Distance of 210 KM both Train meets
  Answer: Option C
  
  Reply
Abdul Samad says:

December 2, 2018 at 3:59 pm

First we have to calculate the time in which both trains will meet:
Chang in Time=Change in distance/change in speed.
Change in distance is 30km. It is because first train at speed of 60km/hr will cover 30km in half hour(30 minutes)
Change in speed is 70-60=10km/hr
So,
T= 30/10
T=3hr
Therefore distance=speedxtime
Put it in below equation:
V1xT+30km=V2xT
60×3+30=70×3
210km=210km

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