A trial balance shows Cash $3,000, share capital $2,000, Fees Earned $1,900, and Supplies Expense. If the trial balance is in balance, what is the Supplies Expense amount?

1. In a balanced trial balance, total debits equal total credits. 2. Credit balances are share capital $2,000 and Fees Earned $1,900, totalling $3,900. 3. Debit balances are Cash $3,000 plus Supplies Expense (an expense has a debit balance). 4. Set debits equal to credits: $3{,}000 + x = 3{,}900$, so $x = 900$. 5. Option C is the total, not the missing figure; option B and D do not balance the columns. 6. Therefore Supplies Expense is $900. _Source: Jonick, Principles of Financial Accounting (CC BY-SA 4.0), §1.3.7 "Trial Balance", p.21_