$3.5$ can be expressed in terms of percentage as:

The difference between a discount of $35 \%$ and two successive discounts of $20 \%$ and $20 \%$ on a certain bill was ₹ $22$. Find the amount of the bill.

If $\frac{3}{5}$ of a number is $23$ more than $50 \%$ of the same number,then what will be $80 \%$ of the number?

If the height of a triangle is decreased by $40 \%$ and its base is increased by $40 \%$,what will be the effect on its area?

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

$23 \%$ of $8040 + 42 \%$ of $545 = ? \%$ of $3000$