Amar bought three articles A, B and C at a price ratio of 2 : 3 : 4 respectively. The total cost was ₹ 81,000. If all the three articles A, B and C were sold for ₹ 1,20,000 at a selling price ratio of 7 : 8 : 9 respectively, then what is the percentage profit he earned by selling A and C?