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Accounts receivables total $250,000 broken down as follows:

0-30 days old = $190,000

31-90 days old = $50,000

over 90 days old = $10,000

The probability of an account going bad based on past history is 0-30 = 2%; 31-90 = 5%; over 90 = 50%.

What should be the ending balance for the allowance for doubtful accounts?