Hello!

It seems to be a pretty easy task, but I don't understand why I get the wrong answer.
The answer from the book is AR = 16 465, but I get a different number. Here is the task (I uploaded it to the google drive as a screen shot):

Farwell Company closes its books monthly. On September 30, selected ledger
account balances are:

Notes Receivable \$37,000
Interest Receivable \$183
Notes Receivable include the following.

Date Maker Face value Terms Interest
______ __________ ___________ _______ ________
Aug. 16 K. Goza Inc. \$12,000 60 days 8%
Aug. 25 Holt Co. 9,000 60 days 7%
Sept. 30 Noblitt Corp. 16,000 6 months 9%

Interest is computed using a 360-day year. During October, the following transactions
were completed:
Oct. 7 Made sales of \$6,900 on Farwell credit cards.
Oct. 12 Made sales of \$900 on MasterCard credit cards. The credit card service charge
is 3%.
Oct. 15 Added \$460 to Farwell customer balances for fi nance charges on unpaid balances.
Oct. 15 Received payment in full from K. Goza Inc. on the amount due.
Oct. 24 Received notice that the Holt note has been dishonored. (Assume that Holt is
expected to pay in the future.)

The question: Enter the balances at October 1 in the accounts receivable accounts. There was no opening balance in accounts receivable. What is the ending balance of accounts receivable.

My computations:

Debit Accounts Receivable:
Oct.7 6,900
Oct. 12 900
Oct. 15 460 (it is said that this was added to customer balances as finance charges)
Oct. 24 9000 (as the note receivable is dishonored, the amount is transferred to AR account)
Oct. 24 51 (9000 * 7% * (29 days / 360 days) = 51 interest on the dishonored note)
________
17 311
Please, help me to find my mistake.
Thank you very much!