The strength of a school increases and decreases in every alternate year by 10 %. It started with increase in 2000, then the strength of the school in 2003 as compared to that in 2000 was : 

75 gm of sugar solution has 30 % sugar in it. Then the quantity of sugar that should be added to the solution to make the quantity of the sugar 70% in the solution is : 

Prashant's monthly income is 30% more than that of Vimal. Vimal's monthly income is 20% less than that of Abhishek. If half of the value of the difference between the monthly income of Prashant and Abhishek is Rs.1800, what is the monthly income of Vimal? 

Mohan gets 3 marks for each correct sum and loses 2 marks for each wrong sum. He attempts 30 sums and obtains 40 marks. The number of sums solved correctly is:

If the price of petrol increases by 19% and Sunitha intends to spend only an additional 12 % on petrol, by what percent should she reduce the quantity of petrol purchased?

Average of ten positive numbers  is x. If each number is increased by 12%  then x is increased by

In an alloy, there is 12 % of copper, to get 69 kg of copper, how much alloy will be required?