Two trains each having a length of 160 meters moving in opposite direction crossed each other in 9 seconds. If one train crossed a 200-metre-long platform in 18 seconds,then the ratio of their speeds is:

9 : 7

Train take 18 seconds to cross 200 m long platform ,

So Speed of train = \(\frac{200 + 160 }{18}\)

= \(\frac{360 }{18}\) = 20 m/sec

Let Speed of another train = A km/h 

Relative speed when they moves in opposite direction = ( 20 + A ) km/h

Distance covered = 160 + 160 = 320 m

Time = 9 sec

Speed = \(\frac{320 }{9}\)

( 20 + A ) = \(\frac{320 }{9}\)

180 + 9A = 320

A = \(\frac{140 }{9}\)

Ratio of their speed is  ,  20 : \(\frac{140 }{9}\)

= 9 : 7