In an examination, 45% of all the students who appeared are boys and the rest are girls. If 60% of the boys and 70% of the girls passed, then what is the percentage of students who failed?

If the duty on an article is reduced by 40% of its present rate by how much per cent must its consumption increase in order that the revenue remains unaltered?

0.15% of of ₹ 10000 is :

If the price of a commodity is decreased by 20% and its consumption is increased by 20%, what will be the increase or de- crease in the expenditure on the commodity?

The price of petrol is increased by 25%. By how much percent a car owner should reduce his consumption of petrol so that the expenditure on petrol would not be increased?

32 is what percentage of 80?

The length of a rectangle is in- creased by 10% and breadth de- creased by 10%. Then the area of the new rectangle is: 

if 20% of A = 50% of B, then what percentage of A is B?