how did they get the answer $25,500?

Given the following information, which is the ending balance in the allowance for doubtful accounts? - Company used percentage of credit sales method for simplicity. - Beginning allowance account had $4,000. - Sales for the period were $1,000,000.25% of sales were paid for in cash. - 3% of credit sales are deemed uncollectible. - One account was written off for $1,000. $20,500 $22,500 $25.500