An article is sold at a discount of $20 \%$ on the marked price. In order to gain $60 \%$ on the marked price,at how much more percent of the discounted price should it be sold?

For a rectangle,the length and breadth are increased by $10 \%$ and $20 \%$,respectively. The percentage increase in area is:

What percentage of numbers from $1$ to $70$ have squares that end in the digit $1$?

If $20 \%$ of $a = b$,then $b \%$ of $20$ is the same as: (in $\%$ of $a$)

From the salary of an officer,$10\%$ is deducted as house rent,$15\%$ of the rest he spends on children's education,and $10\%$ of the balance,he spends on clothes. After this expenditure,he is left with $₹ 1377$. His salary is:

In an examination,$A$ got $25\%$ marks more than $B$,$B$ got $10\%$ less than $C$,and $C$ got $25\%$ more than $D$. If $D$ got $320$ marks out of $500$,the marks obtained by $A$ were: