Answer: The amount debited to Accounts Receivable for the new partnership is $19,500.
Explanation: Note that out of the accounts receivable contribution of $22,500 Jackson made to the partnership, $3,000 is deemed to be completely worthless. This means that $3,000 was already a write-off. The entries that would have been passed to recognize the write-off is Debit Bad debt / provision for doubtful accounts $3,000; Credit Accounts receivable $3,000.
The $1,500 provision for future uncollectible would go in as Debit Bad debt expense $1,500; Credit Provision for doubtful accounts $1,500.
Remember, the question is asking about the amount that will be debited to Accounts Receivable and NOT the net balance to be debited to it, besides the provision to be made is the decision of the partnership not Jackson's, so, $19,500 will be debited to accounts receivable.