I wanted to purchase 10 chairs for the class room whose cost was Rs. 200 each. the trader offered me a discount if I were to purchase a set of 12 chairs. So I calculated that if I assume the normal price of 10 chairs then we can purchase 2 extra chairs which cost me only Rs. 80 each of two chairs at the cost price of 12 chairs after discount. What is the percentage discount?

• 6%
• 8%
• 12%
• 10%