Ratio of CP and SP is 12:13, then the profit percent is?

A man has 60 pens. He sells some of these at a profit of 12 % and the rest at 8 % loss. On the whole, he gets a profit 11 %. How many pens were sold at 12 % profit.

A man buys 12 articles for Rs. 12 /- and sells them at the rate of Rs.1.25 per article. His gain percentage is: 

A trade buys 800 kgs of tomatoes for Rs 7200.  10% tomatoes are damaged in transportation. At what rate (Rs / kg) should he sell the rest earn 30 % profit? 

The cost price of item B is Rs. 150/- more than the cost price of item A. Item A was sold at a profit of 10% and item B was sold at a loss of 20%. If the respective ratio of selling prices of items A and B is 11 : 12, what is the cost price of item B?

The cost price of two items P and Q are equal. If item P sold at 40% profit and item Q sold at 20% less than the selling price of item P, then the total profit is ?

By selling an article for Rs. 700 a man lost 30 %. At what price should he have sold it to gain 30%? 

A sells to B an iron box at 10% profit. B sells it to C for 20% profit. If C pays Rs. 528 then then the cost price of A is