If $\frac{a}{3} = \frac{b}{8}$,then $(a + 3) : (b + 8)$ is equal to

The ratio between two numbers is $2: 3$. If each number is increased by $4$,the ratio becomes $5: 7$. The numbers are:

In an army selection process,the ratio of selected to unselected candidates was $4:1$. If $90$ less had applied and $20$ less were selected,the ratio of selected to unselected candidates would have been $5:1$. How many candidates had applied for the process?

$A$ mixture contains alcohol and water in the ratio $4:3$. If $5 \text{ liters}$ of water is added to the mixture,the ratio becomes $4:5$. Find the quantity of alcohol in the given mixture (in $\text{L}$).

There are three sections $A, B$ and $C$ in a school of class $I$. The ratio of students in sections $A$ and $B$ is $3:5$ and that in $B$ and $C$ is $4:7$. If the total number of students in the class is $201$,then the number of students in section $A$ is:

If $\frac{1}{2}$ of $A = \frac{2}{5}$ of $B = \frac{1}{3}$ of $C$,then $A : B : C$ is