Determine the amount to be added to Allowance for Doubtful Accounts in each of the following cases and indicate the ending balance in each case. (a) Credit balance of $450 in Allowance for Doubtful Accounts just prior to adjustment. Analysis of Accounts Receivable indicates uncollectible receivables of $8,040. Amount added Ending balance (b) Credit balance of $450 in Allowance for Doubtful Accounts just prior to adjustment. Uncollectible receivables are estimated at 2% of credit sales, which totaled $882,000 for the year. Amount added Ending balance