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Assume the following history of our recent relationship with XYZ Co. XYZ was slightly overdue on an account debt to us and offered a $10, 800 note, bearing interest of 10% and due in four months, in payment of the account. We accepted. XYZ forfeited on the note but promised to pay is ASAP. XYZ mailed us a check in payment of the account created on Jan. 1. They included an apology note and voluntary paid us 12% per annum on the balance plus full payment of the account.