Hey so i'm looking to finance a car, and i have some issues with the numbers im getting.

So after all of the fees, taxes, my down payment, the unpaid balance is $8538.67, and i'm new to having credit so the interest rate is pretty high, its at 21%.
So $8538 plus the 21% interest leaves me around $10,300.

The option they gave me is $250 a month for 60 months and 250 x 60 = $15,000. Which seems off if i am to only owe $10,300.

So what im wondering is where did that extra $5,000 come from or am i just calculating things wrong.

Any help would be appreciated! Thanks.