The ratio of $A$'s and $B$'s ages is $4:5.$ If the difference between the present age of $A$ and $B$'s age $5$ years hence is $3,$ then what is the sum of the present ages of $A$ and $B$ (in years)?

The sum of the ages of two brothers, having a difference of $8 \, \text{years}$ between them, will double after $10 \, \text{years}$. What is the ratio of the age of the younger brother to that of the elder brother?

The ratio of the age of Tina and Rakesh is $9:10$. $10 \text{ years}$ ago,the ratio of their ages was $4:5$. What is the present age of Rakesh (in $\text{years}$)?

Ram's present age is three times his son's present age and $\frac{2}{5}$ of his father's present age. The average of the present ages of all of them is $46 \, \text{years}$. What is the difference between the Ram's son's present age and Ram's father's present age? (in $\text{years}$)

$A$ father's age is three times the sum of the ages of his two children,but $20 \, \text{years}$ hence his age will be equal to the sum of their ages. Then,the father's age is (in $\text{years}$)

The ratio between the present ages of $P$ and $Q$ is $5: 7$. If the difference between $Q$'s present age and $P$'s age after $6$ $years$ is $2$,what is the sum of ages of $P$ and $Q$ at present? (in $years$)