Profit

The draft financial statements of Haseen’s business for the year ended 31 July 20X0 show a profit of $54,250 prior to the correction of the following errors:
1. Cash drawings of $250 have not been accounted for.
2. Debts amounting to $420, which were provided against in full during the year, should have been written off as irrecoverable.
3. Rental income of $300 has been classified as interest receivable.
4. On the last day of the accounting period, $200 in cash was received from a customer, but no bookkeeping entries have been made.
What is Haseen’s amended profit for the year ended 31 July 20X2?
A) 53,580
B) 53,830
C) 54,250
D) 55,830
Dear tutor, to my mind the correct answer is 54,250-420=53,830. But correct answer is 54,250.I didn’t understand. Relating to explaination that given in the book “the expense of $420 has already been recorded when the allowance was made during the year”. But i didn’t see anything about allowance. There is no any sentence about allowance. Why this answer is correct? Thanks in advance