Answer:
3/8 fraction
Explanation:
A 2/3 part of the entire car that Rosy waxes with 1/4 part of the bottle of car wax.
If we consider the full bottle of car wax as x, then
Rosy waxes 2/3 of the car with an x/4 bottle of car wax.
If the rate of waxing remains unchanged, then
Rosy will wax full of the car with (x/4)(3/2) =3x/8 bottle of car wax.
Therefore, a 3/8 fraction of the bottle car wax will be used. (Answer)