A long-stay parking lot charges an intimo fee of $10, plus $2 for each day the car is parked. How many days must the car be parked for the average cost per day to fall to $4

The car must be parked there for 5 days

Step-by-step explanation:

Let the number of days be x

For x days, the amount paid would be 10 + 2 (x) = 10 + 2x

now this amount is equal to an average value of $4 per day for same x days. Using the average, the amount of money paid will be $4x

Now since these two values are equal, we equate them

10 + 2x = 4x

10 = 4x - 2x

2x = 10

x = 10/2 = 5 days