Rohit bought 10 packs of pens, which had 5 pens in one pack for Rs. 10 per pack and while selling them he packed them in 5 different pack of 10 pens each and sold them at Rs. 40 per pack. Find the total profit.
Rs. 100
Cost price = (5 pens for Rs. 10) × 10 = Rs. 100
Selling price = (10 pens for Rs. 40) × 5 = Rs. 200
Total profit = Selling price - Cost price = 200 - 100 = Rs. 100