A - Percentage of Accounts Receivable Approach ZELDEN GENERAL SERVICES has been operating for 5 years. It is engaged in various repairs of equipment and furniture and fixtures on cash basis and on account. Shown below are selected ledger accounts as of December 31, 2021: Sale of services during the year (30% are cash sales) P 576,930 Cash collection on accounts receivable 358,700 Accounts Receivable, January 1, 2021 142,850 Allowance for Doubtful Accounts, January 1, 2021 5,350 REQUIRED: Prepare the adjusting entry as of December 31, 2021 under each of the following independent cases: Case 1: 10% of outstanding accounts receivable are estimated to be doubtful of collection. Case 2: The allowance account is to be increased by P13,500. Case 3: The allowance account is to be increased to P7,850