Sonja's credit card has an APR of 21%, calculated on the previous monthly
balance, and a minimum payment of 2%, starting the month after the first
purchase. Her credit card record for the last 7 months is shown in the table
below.
End of Previous New Payment Finance Principal New
month balance charges received charges paid balance
$0.00
$700.00 $0.00 $0.00 $0.00 $700.00
$700.00 $0.00 $14.00 $ 12.25 $1.75 $698.25
$698.25
$0.00
$13.97 $12.22 $1.75 $696.50
$696.50 $0.00 $13.93 $12.19 $1.74 $694.76
$694.76
$0.00 $13.90
$12.16
$1.74
$693.03
$693.03 $0.00 $13.86 $12.13 $1.73 $691.29
$691.29 $0.00 $13.83 $12.10 $1.73 $689.57
About what percentage of Sonja's payments so far have gone to paying
interest?