Two trains A and B start their journey from X and Y respectively towards each other. When they will cross each other then, train A and B will takes 64 hours and 49 hours respectively to reach their destination. The speed of train A is 49 km/hr. Find the distance between X and Y?

5880 km 

\(\frac{S_{A} }{S_{B}}\) = \(\sqrt{\frac{t_{B}}{t_{A}}}\) \(\Rightarrow \) \(\sqrt{\frac{49}{64}}\) \(\Rightarrow \)\(\frac{7}{8}\)

Speed of A \(\Rightarrow \) 7 \(\longrightarrow \) 49 km/h (given)

Speed of B \(\Rightarrow \) 8 \(\longrightarrow \) 56 km/h

now distance \(\Rightarrow \) 49 km/h × 64 hrs + 56 km/h × 49

\(\Rightarrow \) 3136 + 2744

\(\Rightarrow \) 5880 km