The ratio of the number of boys and girls in a school is $8: 12$. If $50 \%$ of boys and $25 \%$ of girls are getting scholarships for their studies,what is the percentage of school students who are not getting any scholarships (in $\%$)?

In a class there are $z$ students. Out of them $x$ are boys. What part of the class is composed of girls?

Two numbers are in the ratio of $5: 8$. If $12$ is added to each,they are in the ratio of $3: 4$. Find the sum of the two numbers.

The ratio of ages between $A$ and $B$ is $6: 5$ and the age of each $C$ and $D$ is $\frac{9}{10}$ times that of $B$. The age of $F$ is less than $A$ but greater than $B$. The ratio of ages between $B$ and $E$ is $2: 3$. Also,the age of $A$ is $3 \text{ years}$ less than $E$. What is the ratio of the ages of $A$ and $F$ if all the ages are integers?

In a college,$150$ students of $MBA$ are enrolled. The ratio of boys to girls is $7:8$. There are three disciplines in the college,namely,Marketing,$HR$,and Finance. In the Marketing discipline,there are $50\%$ girls of their total number and the boys are $40\%$ of their total number. In the $HR$ discipline,girls are $30\%$ of their total number while boys are $30\%$ of their total number. The Finance discipline has girls $20\%$ of their total number and the boys are $30\%$ of their total number. $7$ boys and $9$ girls are in the $HR$ and Marketing both. $6$ boys and $7$ girls are in the $HR$ and Finance both. $5$ boys and $8$ girls are in the Marketing and Finance both. $2$ boys and $3$ girls are enrolled in all the three disciplines. The ratio of boys to girls enrolled only in the $HR$ discipline is:

$A$ certain sum was divided among $P$ and $Q$ in the ratio $5:6$. If $Q$'s share was ₹ $2400$,the total sum was (in ₹):