A shopkeeper marks his goods 30% above the cost price, but allows a 20% discount for cash purchase. What percent profit does he make?

Question: A shopkeeper marks his goods 30% above the cost price, but allows a 20% discount for cash purchase. What percent profit does he make?

Solution:
At 30% above,
The market price of goods = (100 + 30)
= Tk. 130

At 20% discount,
Selling price = 130 - 20% of 130
= 130 - 26
= Tk. 104

∴ Profit = (104 - 100) = Tk. 4
Profit % = (4/100) × 100
= 4%