tparanidharan wrote:
A train X starts from Meerut at 4 p.m. and reaches Ghaziabad at 5 p.m.while another train Y starts from Ghaziabad at 4 p.m. and reaches Meerut at 5:30 p.m. The two trains will cross each other at:
A. 4:36 p.m.
B. 4:42 p.m.
C. 4:48 p.m.
D. 4:50 p.m.
E. 4:52 p.m.
For Train X =>
M (4 PM) ---------------------- G (5 PM) = 1hr
For Train Y =>
G (4 PM) ---------------------- M (5.30 PM) = 1.5 hrs
Now if
Y is travelling at a speed of say
100 kms/hour.
100 km/hr means he can cover 100 kms in an hour. So in his travel time of 1.5 hrs he will cover 150 kms, his complete trip's distance.
Now X will also travel the same distance of 150 kms.
Now to cover 150 kms in 1 hour he will have to travel at a speed of 150 kms/hr.
So from assuming speed Y as 100 kms/hr, we have the following details -
Speed of Train Y = 100 kms / hr
Speed of Train X = 150 kms / hr
Now to find their meeting point, we have total speed = (100 + 150) kms/ hr [As trains are moving towards each other]
and we have total distance of 150 km covered by X and Y when they meet*.
*[As X will come from one direction and Y from other, and when they meet they would be covering the whole track in totality]
Hence,
\( Time = \frac{Distance }{ Speed} = \frac{150}{250}\)
Time = \(\frac{3}{5}\) hours = \(\frac{3}{5} * 60\) = 36 minutes
Hence answer is they will meet 36 mintues after their same starting time. Hence
4:36 pm _________________
Regards,
AD
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