$A$ man is $3 \, \text{years}$ older than his wife and four times as old as his son. If the son becomes $15 \, \text{years}$ old after $3 \, \text{years}$, what is the present age of the wife? (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 $\text{years}$)

The average age of $11$ players of a cricket team is increased by $2$ $months$ when two of them aged $18\, years$ and $20\, years$ are replaced by two new players. The average age of the new players is:

$A$ 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 $\text{years}$)

$7$ years ago,the ages (in years) of $A$ and $B$ were in the ratio $4:5$; and $7$ years hence they will be in the ratio $5:6$. The present age of $B$ is (in years):

$A$ man's age is $125 \%$ of what it was $10 \, \text{years}$ ago, but $83 \frac{1}{3} \%$ of what it will be after $10 \, \text{years}$. What is his present age? (in $\text{years}$)