Two trains running in opposite directions cross a stationary lady standing at point F in 26 seconds and 21 seconds respectively. The two trains cross each other in 24 seconds.
Let the speeds of Train 1 and Train 2 be v1 and v2 respectively.
Let the lengths of Train 1 and Train 2 be L1 and L2 respectively.
When a train passes a stationary person, the train travels a distance equal to its own length.
For Train 1:
L1=v1×26
L1=26v1 ... (1)
For Train 2:
L2=v2×21
L2=21v2 ... (2)
When the two trains cross each other while moving in opposite directions, their relative speed is v1+v2.
The combined distance covered is L1+L2 in 24 seconds.
L1+L2=(v1+v2)×24 ... (3)
Substituting (1) and (2) into (3):
26v1+21v2=24(v1+v2)
26v1+21v2=24v1+24v2
26v1−24v1=24v2−21v2
2v1=3v2
v2v1=23
Therefore, the ratio of the speeds of the two trains is 3:2.