A shopkeeper sells oranges at a price of ₹80 per orange for purchases up to 100 oranges. However, for every additional 10 oranges bought beyond 100, the shopkeeper offers a discount of ₹5 per orange on the entire purchase. The total number of oranges sold is always a multiple of 10. What is the optimal number of oranges the shopkeeper should sell to maximize revenue?

Selling price of 100 pieces of oranges = 100 X 80 = Rs. 8,000 And selling price of 110 pieces of oranges = 110 X 75 = Rs. 8,250 And selling price of 120 pieces of oranges = 120 X 70 = Rs. 8,400 And selling price of 130 pieces of oranges = 130 X 65 = Rs. 8,450 And selling price of 140 pieces of oranges = 140 X 60 = Rs. 8,400 And selling price of 150 pieces of oranges = 150 X 55 = Rs. 8,250 We can see that the total revenue increases till 130 pieces and starts dropping after 130. So, the seller will have maximum revenue on selling 130 oranges.