if , the find the value of x²

The price of jewelry , passing through three hands. rises on the whole by 65 %. If the first and the second sellers earned 20 % and 25 % profit respectively, the profit earned by the third seller is 

O is the incentre of ∆ABC and ∠A = 30° then ∠BOC is

By selling 25 m of cloth a man gains the selling price of 5 m of cloth. Find the gain percent?

On selling an article for Rs.240, a trader loss of 10%.In order to gain 10%, he must sell that article for -

Direction: The following graph shows the number of boys and girls in Class V, Class VI, Class VII and Class VIII. Study the graph and answer the question.

What is the average number of girls in all the classes?

Direction: A shopkeeper has some kg. rice of same price. He sold 150 kg. rice at 25 Rs. per kg. and earned a profit of 25%, another 180 kg. rice is sold at a profit of 20% and rest are sold at a loss of 10%. If the shopkeeper earns Rs. 1230 profit on all the rice that he has sold then answers the following question:

If the shopkeeper earns 10% profit instead of 10% loss on the rest rice then find the difference between the old and new profit. 

A principal increase by 50 percent in five years at the rate of simple interest. What will be the compound interest for 3 years at Rs 20,000 with the same interest rate?