$A$ father is now $3$ times as old as his son. $5$ years back,he was $4$ times as old as his son. The age of the son is:

Radha's present age is $3 \text{ years}$ less than twice her age $12 \text{ years}$ ago. Also,the ratio of Raj's present age to Radha's present age is $4:9$. What will be Raj's age after $5 \text{ years}$? (in $\text{years}$)

In a family,mother's age is twice that of daughter's age. Father is $10 \,years$ older than mother. Brother is $20 \,years$ younger than his mother and $5 \,years$ older than his sister. What is the age of the father? (in $years$)

$3 \text{ years}$ ago,the average age of a family of $5$ members was $17 \text{ years}$. $A$ baby having been born,the average age of the family is the same today. What is the age of the child? (in $\text{years}$)

The ratio of the present age of Manoj to that of Wasim is $3:11$. Wasim is $12 \text{ years}$ younger than Rehana. Rehana's age after $7 \text{ years}$ will be $85 \text{ years}$. What is the present age of Manoj's father,who is $25 \text{ years}$ older than Manoj? (in $\text{years}$)

The ratio of the present ages of $Ram$ and $Rakesh$ is $6:11$. $4$ years ago,the ratio of their ages was $1:2$. What will be $Rakesh$'s age after $5$ years? (in years)