Question 1159973
He has gone 0.25 of the distance, but has 24 km more before going 1/3 the distance.  So 24 = (0.33333 - .25)X, 24 = .08333X,  X = 288 miles for the journey.

So he has to travel 2/3 of the way for the entire journey, 2/3X = 192 km left to go.