What percentage is equivalent to $5 \frac{1}{4}$?

$A$ number is increased by $84$,it becomes $107 \%$ of itself. What is the number?

$40 \%$ of $20 \% + 30 \%$ of $25 \% + 50 \%$ of $28 \%$ is equivalent to:

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 $2009$?

The average marks obtained in a class of $50$ students is $70 \%$. The average of the first $25$ students is $60 \%$ and that of the next $24$ students is $80 \%$. What is the percentage of marks obtained by the last student?

In a class,$70 \%$ of the students read Hindi,$40 \%$ of the students are boys,and $20 \%$ of the girls do not read Hindi. What percentage of boys read Hindi?