Question

The ratio between the speeds of two trains is 7 : 8. If the second train runs 400 km in 4 hours, then the speed of the first train is:

Answer 1

Let the speed of two trains be 7xkm/hr and 8x km/hr

So, 8x=400/4 = 100 therefore x= 100/8 = 12.5

Hence speed of first train= 7*x=7*12.5 = 87.5 km/hr