Question 902559
let the speed of the train be x km/h

distance between AB = 45/60 * x

speed decreased by 5 km/h

speed = (x-5)

d= (x-5) * 48/60 km

But d is same 

so

45/60 * x = 48/60*(x-5)

45x=48x-240

3x=240
/3
x= 80

speed of train is 80 km/h
time = 45 minutes = 3/4 hour

d=rt

80*3/4

=60 km

Distance between A & B = 60 km