pbls ledger control a/c reconcilation

Hallo,

I have the following example from an F3 book, and I don’t understand why item 1 (purchase returns below) is not used to get the answer. I am wondering, if you have some idea, is this a mistake or there’s some reasoning for it?

Example:
The total of the list of balances in the payables ledger of Bounce on 30 June 2010 was $289,500. This balance did not agree with the payables ledger control account balance.

The following errors were discovered.
1 The total of purchases returns was undercast by $3,000.
2 A contra entry of $690 was recorded in the payables ledger control account but not in the payables ledger.
3 An invoice for $8,720 was recorded in the supplier’s account as $7,820.

What amount should Bounce record in its statement of financial position as the amount of trade payables as at 30 June 2010?

Solution:

Total of payables ledger balances 289,500
Contra entry not recorded in payables ledger (690)
Invoice under-stated in payables ledger (8,720 – 7,820) 900
Adjusted balance 289,710.

Thank you!