The number of cars (c) in a parking lot increases when the parking fee (f) decreases. Write the correct equation for this scenario, and solve for the number of cars when the fee is $6. Fee Cars 20 15 30 10 c = − 300 over f c = −50 c = 300 over f c = 50 c = 3f c = 18 c = 3f; c = 2