To find the cost of goods sold using the gross profit margin, we need to know the formula which is:
Gross profit margin = Gross profit / Sales
We have the gross profit margin as 20% and the sales as N10,600.
20% of sales = 20/100 * N10,600 = N2,120 (this is the gross profit)
Next, we need to use the formula:
Gross profit = Sales - Cost of goods sold
We know the sales is N10,600 and we need to find the cost of goods sold.
N2,120 = N10,600 - Cost of goods sold
Therefore, Cost of goods sold = N10,600 - N2,120 = N8,480
So, the cost of goods sold is ₦8,480. Option B is the correct answer.