What part of the path is left for the car to travel if it has traveled 20% of the intended path?

The entire planned path that the car was originally going to drive is 100%.

The car has already covered 20% of the planned path.

That is, the car still has to pass:

100 – 20 = 80% of the total planned path.

In the case of expressing the remainder of the distance that the car must still travel as a fractional number, it will look like this: 80/100, that is, it remains to drive 80 percent of 100.

It remains only to reduce the given fractional number:

80/100 = 8/10 = 4/5.

Decimal: 0.8