There are two different ways we can read your question.
Each way has a different answer.
Here it is both ways:
Way #1: (12 + 4n) / 3 = 8
Multiply each side by 3 : 12 + 4n = 24
Subtract 12 from each side: 4n = 12
Divide each side by 4: n = 3 .
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Way #2: 12 + 4n/3 = 8
Subtract 12 from each side: 4n/3 = -4
Multiply each side by 3: 4n = -12
Divide each side by 4: n = - 3
