No. The question explicitly says the $54,000 effective gross income is already after the vacancy allowance. Subtract the stated operating expenses once: $54,000 - $18,000 = $36,000 NOI.

Deducting vacancy again counts the same reduction twice. First identify the level of income supplied: potential gross income is before vacancy; effective gross income has already accounted for the stated vacancy and collection losses. Include other income only when the question supplies it or says it belongs in that figure.

A useful note beside your calculation is simply 'vacancy already deducted.' That prevents you from reusing every percentage mentioned in a longer problem. For a case starting one step earlier, use the worked rent-to-NOI exercise. The BOE income-processing lesson explains the difference between the income levels.