A shopkeeper purchased 59 dozens of articles at the rate of ₹520 per dozen. He sold each one of them at the rate of ₹52. What percentage profit did he make?

Correct option is D

Given
Cost Price of 59 dozens = ₹520 per dozen
Selling Price of 1 article = ₹52
Formula Used
Profit = Selling Price - Cost Price
Profit Percentage = $$\frac{Profit}{Cost Price} \times$$​ 100
Solution
Cost Price of 1 dozen (12 articles) = ₹520
Cost Price of 1 article = $$\frac{520}{12} = \frac{130}{3}$$​​
Selling Price of 1 article = 52
Profit on 1 article = $$52 - \frac{130}{3} = \frac{156 - 130}{3} = \frac{26}{3}$$​​
Profit Percentage =$$\frac{26/3}{130/3} \times 100$$​​
Profit Percentage = $$\frac{26}{130} \times 100 = \frac{1}{5} \times 100 = 20\%$$​​
Final Answer
So the correct answer is (d) 
Exam Hall Method