Super Corp. reported credit sales of $2,000,000, cash sales of $200,000 and bad debt write-offs of $100,000for last year. The ending balance in accounts receivable was $4,500,000. The bad debt expense was $250,000. The allowance for doubtful accounts had a balance of $400,000 at the beginning of the year. What was the balance in the allowance for doubtful accounts at the end of the year?