Answer:
The adjustment balance will be of 18,000
Explanation:
We should build Accounts Receivables T-account to get the adjusted balance:
Accounts Receivables
DEBIT CREDIT
15,000 UNADJUSTMENT
3,000 ADJUSTMENT
18,000 ADJUSTED BALANCE**
**As the adjustment is in the same side as the unadjusted balance, we add it. So we end up with 15,000 + 3,000 = 18,000