Suppose one bus travels at x km/h, the second bus is 17 km/h slower so it is x-17 the first bus travels a total of 7x km, the second bus travels 7(x-17)km, together they travel the total distance of 1631 km 7x + 7(x-17) =1631 7x + 7x -119 =1631 14x=1750