Here is a question and its answer, I want to know how can we figure the highlighted interest in the answer ($15) and howcome there is an interest since #2 in the question says at the end "no interest has been accrued".

Practice Problem 387 PRACTICE PROBLEM Poorten Company's bank statement for May 2017 shows the following data. Prepare hank reconciliation and journatize entries LO 3) Balance 5/1 Debit memorandum: $12,650 Balance 5/31 $14,280 Credit memorandum: NSF check $175 Collection of note reccivable $505 The cash balance per books at May 31 is $13,319. Your review of the data reveals the following 1. The NSF check was from Copple Co., a customer 2. The note collected by the bank was a $500, 3-month, 12% note. The bank charged a $10 collection fec. No interest has been accrued 3. Outstanding checks at May 31 total $2,410 4. Dcposits in transit at May 31 total $1,752. 5. A Poorten Company check for $352, dated May 10, cleared the bank on May 25. The company recorded this check, which was a payment on account, for $325 Instructions (a) Prepare a bank reconciliation at May 31 (b) Journalize the entries required by the reconciliation. Solution POORTEN COMPANY Bank Reconciliation May 31, 2017 Cash balance per bank statement Add: Deposits in transit Less: Outstanding checks Adjusted cash balance per bank Cash balance per books $14,280 1,752 16,032 2,410 $13,622 $13,319 Add: Collection of note receivable $500, plus $15 less collection fee $10 505 13,824 Less: NSF check $175 27 Error in recording check 202 Adjusted cash balance per books $13,622 May 3 Cash 505 10 Miscellaneous Expense Notes Receivable Interest Revenue 500 (To record collection of note by bank) 31 Accounts Receivable -Copple Co. 175 (To record NSF check from Copple Co) 31 Accounts Payable Cash 27 27 (To correct error in recording check)