Since Marnie has bought her car, the value has gone down 15%. If her car is 13000 right now, how much was it worth when she bought it?

Percentage of depreciation of the car that Marie bought = 15%

Present value of the car = 13000

Let us assume that the value of the car at the time of buying = x

So

The percentage valuation of the car now = (100 - 15) percent

= 85 percent

Then

(85/100) * x = 13000

85x = 13000 * 100

85x = 1300000

x = 1300000/85

= 15294.12

So the actual cost of the car is 15294.12. I hope the procedure is clear enough for you to understand.