Answer:
$105,000
Explanation:
The journal entries to record and adjust the transactions should be as follows:
Writing off bad debt:
Dr Allowance for doubtful accounts 210,000
Cr Accounts receivable 210,000
that leaves the balance of allowance for doubtful accounts at $180,000 - $210,000 = -$30,000 or $30,000 debit balance.
the adjusting entry made at the end of the year ($4,500,000 x 3%):
Dr Bad debt expense 135,000
Cr Allowance for doubtful 135,000
the balance for allowance of doubtful accounts = $135,000 - $30,000 = $105,000