Let x be the number of miles the driver still has to travel.
The driver traveled 120 + 120/4 + 120/42/3 = 120 + 30 + 40 = 190 miles.
So the remaining distance is x + 190 = 55 + 1 2/3 * x
Multiplying both sides by 3/2 gives 3/2x + 3/2190 = 3/255 + 3/2*x + x
This simplifies to x = 190.
Therefore, the driver still has to travel 190 miles.