Answer:
Step-by-step explanation:
As it is supposed to be linear, we just subtract two adjacent months to find the difference.
$13,849.60 - $13,610.81 = $238.79 which will be her monthly payment (Q 14)
December's balance is $13,610.81 - $238.79 = $13,372.02 (Q13)
At the end of September, her first payment, her balance was
$13,849.60 + $238.79 = $14,088.39 and her original purchase price was
$14,088.39 + $238.79 = $14,327.18
so an equation for the current balance B at any month m is
B = (-$238.79)m + $14,327.18
We verify this by testing for February
B = (-$238.79)6 + $14,327.18 = $12,894.44 which checks out
It will take 14327.18 / 238.79 = 60 months to pay it off or 5 years (Q 15)