If $A$'s salary is $30\%$ more than that of $B$,then by how much percent is $B$'s salary less than that of $A$ (in $\%$)?

$A, B$ and $C$ start a business by investing $Rs. 70000$ that earns them a profit of $Rs. 42000$ at the end of the year. $A$ invests his share in the profit in a scheme that gives $10\%$ interest compounded annually and $B$ invests his share in a scheme that gives $20\%$ interest compounded annually. $A$ gets $Rs. 2520$ as interest at the end of $2$ years and $B$ gets an interest of $Rs. 4200$ at the end of one year. Find $C$'s investment in the business.

$60 \%$ of $264$ is the same as:

In $2009$,the food production was $5.5$ million tonnes and in $2010$,the production was $4.4$ million tonnes. Find out the percentage decrease in food production in these two years?

In Jamshedpur,only two newspapers,Dainik Jagran and Prabhat Khabar,are published. It is known that $25 \%$ of the city population reads Dainik Jagran and $20 \%$ reads Prabhat Khabar,while $8 \%$ reads both the newspapers. It is also known that $30 \%$ of those who read Dainik Jagran but not Prabhat Khabar look into advertisements,$40 \%$ of those who read Prabhat Khabar but not Dainik Jagran look into advertisements,and $50 \%$ of those who read both the newspapers look into advertisements. What is the percentage of the population who read an advertisement?

In a recent survey,$40 \%$ of houses contained two or more people. Of those houses containing only one person,$25 \%$ had only a male. What is the percentage of all houses that contain exactly one female and no males (in $\%$)?