Question 330466

I have assumed Car B rate as 70 km/hour instead of 7 which looks practical. If not then replace 70 with 7 and you will get the desired answer.

Car A 60 km/hour
car B 70 km/hour
..
Let Car A travel x km in the time car b travels 260-x

x/60 = 260-x/70
70x=60(260-x)
70x=15600-60x
70x+60x=15600
130x= 15600
x= 120 km
speed of car A = 60 km/hour
120/60 = time 
=2 hours.

They will be 260 km apart after 2 hours