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

A man sold 18 cots for Rs.16800, gaining there by the cost price of 3 cots. The cost price of a cot is 

What is the discount rate of a gift whose selling price is Rs. 420 after a reduction of Rs. 60 on its marked price ?

A car worth Rs 30,000 was sold by A to B at 10 % profit. B sold the car back to A at 5 % loss. In the entire transaction.

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

Vinayak bought an item and sold it at a loss of 5%. If he had bought it for 10% less and sold it for Rs.390 more, he would have had a profit of 20%, find the cost price of item.

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?

A and B invest in a business in the ratio 3:2. If 5% of the total profit goes to charity and A’s share is Rs.855, the total profit is: