A shopkeeper bought 180 pens for ₹1200 and sold them at ₹9 each. What is the percentage profit?   0.1

Step 1: Calculate the cost price per pen

The shopkeeper bought 180 pens for ₹1200. So, the cost price per pen is ₹1200/180 = ₹6.67

Step 2: Calculate the selling price per pen

The shopkeeper sold each pen for ₹9.

Step 3: Calculate the profit per pen

The profit per pen is the selling price minus the cost price. So, the profit per pen is ₹9 - ₹6.67 = ₹2.33

Step 4: Calculate the profit percentage

The profit percentage is the profit per pen divided by the cost price per pen, multiplied by 100. So, the profit percentage is (₹2.33/₹6.67) * 100 = 34.93%

So, the shopkeeper made a profit of approximately 35%.