Final answer:
To find the profit or loss percentage on the whole transaction, the selling price of the two articles needs to be considered. Assuming each article is sold for $100, the selling price is equal to the cost price, resulting in no profit or loss.
Therefore, the correct answer is: C. 4% profit
Step-by-step explanation:
To find the profit or loss percentage on the whole transaction, we need to consider the selling price of the two articles. Let's assume the selling price of each article is $100. One article is sold at a 20% loss, which means it is sold for 80% of its cost price. So the selling price of the first article is $100 x 80% = $80.
The other article is sold at a 20% profit, which means it is sold for 120% of its cost price. So the selling price of the second article is $100 x 120% = $120.
The total selling price of both articles is $80 + $120 = $200. The total cost price of both articles is $100 + $100 = $200. Since the selling price is equal to the cost price, there is no profit no loss on the whole transaction.