In a mixture of $60 \ L$,the ratio of milk and water is $2:1$. What quantity of water (in $L$) should be added so that the ratio becomes $1:3$?

The ratio of the earnings of $A$ and $B$ is $4 : 7$. If the earnings of $A$ increase by $50\%$ and those of $B$ decrease by $25\%$,the new ratio of their earnings becomes $8 : 7$. What are $A$'s earnings?

$Rs. 366$ are divided among $A, B$ and $C$ such that $A$ gets $\frac{1}{2}$ as much as $B$ and $C$ together,and $B$ gets $\frac{2}{3}$ as much as $A$ and $C$ together. What is the share of $A$ (in $Rs.$)?

If $x: y = 2: 1,$ then $(x^{2} - y^{2}) : (x^{2} + y^{2})$ is

If $U: V = 6: 7$ and $V: W = 21: 6$,then find $U: V: W$.

At present,Kavita is twice Sarita's age. $8 \ yr$ hence,the respective ratio between Kavita's and Sarita's ages will be $22:13$. What is Kavita's present age (in $yr$)?