The formula for the lateral surface area of a right circular cone is:

where r is the radius of the base, and l is the slant height.
Plugging in the values we get:
This is completely wrong for logical and mathematical reasons, but for the sake of time I will go over the mathematical reason.
Because all percentages are out of 100, nothing can physically be over 100%, though it is used frequently in hyperbolic sentences and exaggerated statements.
Hope I helped and good luck!
Answer:
520 cars
Step-by-step explanation:
Let the car sold in March be x, x+5%*x=546. (105/100)*x=546. x=520