Places Meerut and Agra are 693 kms. apart.  Train A leaves from Meerut for Agra and Train B leaves from Agra for Meerut at the same time on the same day on parallel tracks.  Both trains meet after 8 hours 15 minutes.  The speed of B is 20 km/h more than that of A.  What is the speed (in km/h) of B?

52

Let, speed of A = x km/h

Speed of B = x + 20 km/h

Both trains are running in opposite directions.

\(\frac{693}{x + x + 20}\) = \(\frac{33}{4}\)

2x + 20 = 21 × 4

2x = 64

x = 32

Speed of B = x + 20 = 32 + 20 = 52 km/h