An ore contains $23 \%$ copper. To get $69 \text{ kg}$ of copper, the quantity of the ore required is: (in $\text{ kg}$)

Out of his total income,Mr. Kapur spends $20 \%$ on house rent and $70 \%$ of the rest on household expenses. If he saves $₹ 1,800$,what is his total income?

If $A$'s income is $25 \%$ less than that of $B$,then how much per cent is $B$'s income more than that of $A$?

Two numbers $A$ and $B$ are such that the sum of $6\%$ of $A$ and $4\%$ of $B$ is two-thirds of the sum of $6\%$ of $A$ and $8\%$ of $B$. Find the ratio of $A:B$.

What percentage is equivalent to $5 \frac{1}{4}$?

In an election between two candidates,one got $55 \%$ of the total valid votes,and $20 \%$ of the total votes were invalid. If the total number of votes polled was $7500$,what was the number of valid votes that the other candidate received?