Two vehicles, named as 'X' and 'Y', travel along side-by-side paths but in opposite directions. The length of vehicle 'Y' surpasses that of 'X' by 12.5%. Their speeds are recorded at 72 km/h for 'X' and 14 m/s for 'Y'. Given that it takes them 50 seconds to fully pass one another, determine the length of 'Y'.