The ratio of the present ages of Swati and Trupti is $4:5.$ $6 \text{ years}$ hence the ratio of their ages will be $6:7.$ What is the difference between their ages? (in $\text{years}$)

$Q$ is as much younger than $R$ as he is older than $T.$ If the sum of the ages of $R$ and $T$ is $60 \text{ years},$ what is definitely the difference between $R$ and $Q$'s age? (in $\text{years}$)

$15$ years hence,Rohit will be just four times as old as he was $15$ years ago. How old is Rohit at present?

The ratio between the ages of Arun and Deepak at present is $4:3$. After $6$ years,Arun's age will be $26$ years. What is the age of Deepak at present? (in years)

Shan is $55$ years old. Sathian is $5$ years junior to Shan and $6$ years senior to Balan. The youngest brother of Balan is Devan,and he is $7$ years junior to him. What is the age difference between Devan and Shan (in years)?

$A$ man is $24$ years older than his son. In $2$ years,his age will be twice the age of his son. The present age of the son is (in years):