What percent of ₹ $2650$ is ₹ $1987.50$?

Two numbers are $10\%$ and $25\%$ lesser than a third number. By what percentage must the second number be increased to make it equal to the first number (in $\%$)?

$23 \% \text{ of } 6783 + 57 \% \text{ of } 8431 = ?$

$45 \%$ of $750 - 25 \%$ of $480 = ?$

$88 \%$ of $370 + 24 \%$ of $210 - ? = 118$

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