Express $\frac{7}{8}$ as a percentage.

The length of a rectangle increases by $20 \%$ and the breadth by $30 \%$. Then the perimeter of the rectangle will increase by:

The salary of a person was reduced by $10 \%$. By what percent should his reduced salary be raised so as to bring it at par with his original salary (in $\%$)?

What percent of $7.2 \,kg$ is $18 \,g$?

The population of Delhi increases by $10 \%$ every year. If the current population of Delhi is $1,331,000$,what was its population $3$ years ago?

Due to a price hike of $20 \%$, $4 \text{ kg}$ less sugar is available for $₹ 120$. What is the initial price per kg of sugar (in $\text{ per kg}$)?