The reduction of Rs . 12 in the selling price of an article will changes 5 % gain into  $$ 2{1\over 2}\% $$ loss . The cost price of the article is 

A person bought pens at 25 for a rupee and sold at 15 for a rupee. What is his profit percentage? 

If shopkeeper sold the mobile for Rs.15000 and then he gets some loss. If he sold the same mobile at Rs.19200 and then he gets profit is double of loss. Find the cost price of the mobile?

A scientist mixes 10% water in his solution but he is not content with it so he again mixes 10% more water in the previous mixture. What is the profit percentage of the scientist if he sells it at cost price:

A shopkeeper marked the price of an article by 40% above cost price and gave discount of Rs. 224. On the final amount, he charged 10% tax. In the whole transaction, he earned Rs. 158.6. Find cost price of the article.

If the cost of production of an article is 2/5 of its marked retail price, If it is sold at 10 % discount then what will be profit ? 

If the selling price of a product is multiplied by 2, the resulting profit is 6 times the original profit. What is the original profit percentage?

Due to increase in the value of eggs by 20 percent, two eggs started getting less at Rs. 24. The current price per dozen of eggs.