Question

Please help me get out of this riddle!

Answer 1

Let distance between calcuta and bombay be x
Let the two trains meet after time t. 
Distance travelled by calcuta mail = d
Distance travelled by bombay mail = x - d
Now d / t = 48. -(1)
x - d / t = v  - (2) ( v is speed of bombay mail)
Divide (2) by (1) (x-d)/d = v / 48
v = (x-d)*48/v -(3)
After meeting the calcuta mail will travel distance  (x-d) in 12 hr
(x-d) / 12 = 48
(x-d)=12*48
Similarly d = 3*v
Substitute values of d and (x-d) in eqn 3 and u will get the answer

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