$A$ district has $64000$ inhabitants. If the population increases at the rate of $2 \frac{1}{2} \%$ per annum,then the number of inhabitants at the end of $3$ years will be...

The production of a company has ups and downs every year. The production increases for two consecutive years consistently by $15 \%$ and in the third year it decreases by $10 \%$. Again in the next two years it increases by $15 \%$ each year and decreases by $10 \%$ in the third year. If we start counting from the year $1998$,approximately what will be the effect on the production of the company in $2002$?

An article is sold at a discount of $20 \%$ on the marked price. In order to gain $60 \%$ on the marked price,at how much more percent of the discounted price should it be sold?

Rajiv spends $20 \%$ of his salary on food,$15 \%$ on conveyance,$10 \%$ on education,and $35 \%$ on house rent. If he spends $Rs. 1950$ on education,how much does he spend on conveyance?

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

If $x$ is $90 \%$ of $y,$ then what per cent of $x$ is $y$?