$A$ number increased by $22 \frac{1}{2} \%$ gives $98$. The number is

$0.025$ in terms of rate per cent is:

$88 \%$ of $370 + 24 \%$ of $210 - ? = 118$

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 $2002$?

The average marks obtained in a class of $50$ students is $70 \%$. The average of the first $25$ students is $60 \%$ and that of the next $24$ students is $80 \%$. What is the percentage of marks obtained by the last student?

In a class,$70 \%$ of the students read Hindi,$40 \%$ of the students are boys,and $20 \%$ of the girls do not read Hindi. What percentage of boys read Hindi?