.
Time taken by two trains running in opposite directions to cross a man stading on the platform
in 28 seconds and 18 seconds respectively. It took 26 seconds for the trains to cross each other.
What is the ratio of their speeds?
a)2:3 b)3:2 c)1:4 d)4:1
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Train 1 length = x meters; train 2 length = y meters;
Train 2 speed = u m/s; train 2 speed = v m/s.
We are given that
= 28 (seconds);
= 18 (seconds).
Also, we are given
= 26 seconds.
It implies x = 28u; y = 18v; = 26.
From the last equation
28u + 18v = 26u + 26v,
28u - 26u = 26v - 18v,
2u = 8v
=
= 4.
ANSWER. The ratio of their speeds is u/v = 4,
or : = 4.
Solved.