Effect of doubtful accounts on net income During its first year of operations, Mack's Plumbing Supply Co. had sales of $6,740,000, wrote off $48,600 of accounts as uncollectible using the direct write-off method, and reported net income of $712,500. Determine what the net income would have been if the allowance method had been used and the company estimated that 1% of sales would be uncollectible