$15 \%$ of $10 \%$ of $20 \%$ of $1000$ is?

$A$ man's wages were decreased by $50 \%$. Again,the reduced wages were increased by $50 \%$. He has a loss of:

There is a ratio of $5:4$ between two numbers. If $40\%$ of the first number is $12$,then what would be $50\%$ of the second number?

In a college election between two candidates,one candidate got $55 \%$ of the total valid votes. $15 \%$ of the votes were invalid. If the total votes were $15,200$,what is the number of valid votes the other candidate got?

Two numbers are respectively $12 \frac{1}{2} \%$ and $25 \%$ more than a third number. The first number is what percentage of the second number?

If $12 \%$ of $x$ is equal to $6 \%$ of $y,$ then $18 \%$ of $x$ will be equal to how much per cent of $y$ ?