Explanation:
it says "college" in the headline of this question.
are you serious ?
this is an upper elementary or beginning of middle school problem.
if you have a problem with such a question in college, you really have a problem and would need intensive tutoring (you need to recover everything from the beginning of math).
in such problems, to find your way, always try to find the amount represented by 1 unit.
everything else can be then calculated in relation to that one unit.
3 cars cost $2.46
1 car costs therefore 1/3 of that :
2.46/3 = $0.82
and 25 cars cost then 25 times that of a single car :
0.82 × 25 = $20.50
in short, the direct approach is
$2.46 × 25/3 = $20.50