$25 \%$ of $25 \% = ?$

Mr. Shamin's salary increases every year by $10 \%$ in June. If there is no other increase or reduction in the salary and his salary in June $2011$ was $Rs$ $22,385$,what was his salary in June $2009$?

About $8 \%$ of the voters in an election did not cast their votes. In this election,there were only two candidates. The winner,by obtaining $48 \%$ of the total votes,defeated his contestant by $1100$ votes. The total number of voters in the election was:

$15 \%$ of $10 \%$ of $20 \%$ of $1000$ is?

For admission in a postgraduate program of Calcutta University,$90 \%$ of the candidates who appeared for the written test were males and the rest were females. $60 \%$ of the males and $80 \%$ of the females passed the written test. What is the total number of students who appeared for the written test,if the total number of passed candidates was $1240$?

$A$ housewife saved $₹ 2.50$ in buying an item on sale. If she spent $₹ 25$ for the item,approximately what percentage did she save in the transaction?