$25 \%$ of $25 \% = ?$

$0.005 = (-?-)*$

If $₹ 2800$ is $\frac{2}{7}$ percent of the value of a house,the worth of the house (in $₹$) is

The length of a rectangle is increased by $30 \%$ and the breadth by $20 \%$. Then the perimeter of the rectangle will increase by what percent?

The price of rice has been increased by $20 \%$. By what per cent should Sanjay reduce the consumption of rice in the family so that the expenditure on rice remains the same as before the increase in the price of rice?

In a recent opinion poll held during April,$60 \%$ of the respondents favoured India Against Corruption $(IAC)$ while the rest favoured Indian political parties $(IPP).$ It was found in May polls that $10 \%$ of $IAC$ supporters switched their preference to $IPP,$ while the same percentage of $IPP$'s supporters also switched their preference to $IAC.$ What percentage of the electorate should now switch their preference from $IAC$ to $IPP$ so that they are at par?