A seller marks his goods 30% above their cost price but allows 15% discount for cash payment. His percentage of profit when sold in cash, is?

Let CP of the goods = ₹ N
∴ Marked price of the goods = N x {(100 + 30)/100} = ₹ 13N/10
Now, SP of the goods = (13N/10) x (100 - 15/100)
= (13N/10) x (85/100) = ₹ 221N/200
⇒ Profit = {(221 x N)/200} - N = ₹ 21N/200
Hence, profit per cent = [{21N/200} /N] x 100 % = 2100/200 = 10.5 %