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

$A$ scored $30\%$ marks and failed by $15$ marks. $B$ scored $40\%$ marks and obtained $35$ marks more than that required to pass. The pass percentage is: (in $\%$)

If $8 \%$ of $x = 4 \%$ of $y,$ then $20 \%$ of $x$ is:

Two numbers are less than a third number by $30 \%$ and $37 \%$ respectively. How much per cent is the second number less than the first (in $\%$)?

At an election,a candidate got elected by fetching $63 \%$ of the total votes. If $54982$ voters did not vote in favour of the elected candidate,what was the total number of votes polled?

$A, B, C$ are three students. $A$ got $18 \%$ more marks than $B$ and $12 \%$ less than $C$. If $B$ got $220$ marks,how many marks did $C$ get?