If $35 \%$ of a number is $12$ less than $50 \%$ of that number,then the number is:

$A$ businessman imported laptops worth $Rs$ $210,000$,mobile phones worth $Rs$ $100,000$,and television sets worth $Rs$ $150,000$. He had to pay $10\%$ duty on laptops,$8\%$ on phones,and $5\%$ on television sets. How much total duty (in Rupees) did he have to pay on all items as per the above details?

$A$'s salary is $20 \%$ less than $B$'s salary. Then $B$'s salary is more than $A$'s salary by:

The price of sugar is reduced by $2 \%$. How many $kg$ of sugar can now be bought for the money which was sufficient to buy $49$ $kg$ of sugar earlier?

In an election between two candidates,$10 \%$ of the voters did not cast their vote. $10 \%$ of the votes polled were found invalid. The successful candidate received $54 \%$ of the valid votes and won by a majority of $1620$ votes. The total number of voters enrolled on the voter's list was:

$x \%$ of $y + ? \%$ of $x = x \%$ of $(x + y)$