$a \%$ of $b + b \%$ of $a =$

In Mumbai,$60 \%$ of the registered voters are $BJP$-supporters and the rest are Congress-supporters. In a mayoral race,if $75 \%$ of the registered voters who are $BJP$-supporters and $20 \%$ of the registered voters who are Congress-supporters are expected to vote for candidate $X$,what percent of the registered voters are expected to vote for candidate $X$?

Which one of the following shows the best percentage?

$A$ jar contains $10$ red marbles and $30$ green ones. How many red marbles must be added to the jar so that $60 \%$ of the marbles will be red?

If the numerator of a fraction is increased by $120 \%$ and the denominator is also increased by $350 \%$,then the fraction becomes $\frac{11}{27}$. What was the original fraction?

The price of an article is cut by $20 \%$. To restore it to its original price,the new price must be increased by: