The speed of a superfast train, T₁ is 20% more than the speed of another superfast train T₂. Both the trains start from point N at the same time and reach point M at the same time. N and M are 500 km apart. T₁ stops for 10 minutes on the way to M, but T₂ covers the distance without any stops en route. What is the speed of T₁ ?

600 km/h

Ratio of speed of T1 to T2 = 6 : 5

Ratio of time                    = 5 : 6

Difference in time = Time for which T1 takes rest

( 6 - 5 ) R = 10 minutes

1R = 10 minutes

So , Time taken by T2 = 6 × 10 = 60 minutes = 1 hour

Speed = \(\frac{Distance}{Speed}\)

= \(\frac{500}{1 }\) = 500 km/h

As , 5R = 500

So , 6 R = 6 × 100 = 600 km/h

So , Speed of T1 is 600 km/h