A shopkeeper allows 10% discount on the marked price of an article and still gains 17%. If he gives 15% discount on the marked price, then his profit percent is:

10.5

        CP                    MP

      100 - D%           100 + P%

     100 - 10%           100 + 17%

         90                      117

Discount offered 15% on the MP = 

Selling price = 85% of the marked price = 85% of 117 = 99.45

Profit%= (99.45 - 90 ) × \(\frac{100}{90}\) = 10.5%