Respuesta :
$200 represents the original fee. Then:
$200 = .10($200) + .25($200) + final payment
$200 = 0.30($200) + final payment
$200 - $60 = final payment
final payment is $140.
$200 = .10($200) + .25($200) + final payment
$200 = 0.30($200) + final payment
$200 - $60 = final payment
final payment is $140.