The average age of a family of $6$ members is $22 \text{ years}$. If the age of the youngest member is $7 \text{ years}$,then what was the average age of the family at the birth of the youngest member?

On $24^{\text{th}}$ May,$2008$,the maximum temperatures of Delhi,Kolkata,and Mumbai were recorded as $35^{\circ}C$,$33^{\circ}C$,and $34^{\circ}C$ respectively. What was the maximum temperature of Chennai so that the average maximum temperature of those four cities would be $35^{\circ}C$ (in $^{\circ}C$)?

Find the average of all the numbers between $6$ and $34$ which are divisible by $5$.

The average weight of $24$ students in section $A$ of a class is $58 \,kg,$ whereas the average weight of $26$ students in section $B$ of the same class is $60.5 \,kg$. Find out the average weight of all the $50$ students of the class. (in $kg$)

The average weight of $6$ persons is increased by $5 \, kg$ when one of them who weighs $40 \, kg$ is replaced by a new man. The weight of the new man is (in $kg$):

The average expenditure of a man for the first five months is $Rs.\, 3600$ and for the next seven months it is $Rs.\, 3900$. If he saves $Rs.\, 8700$ during the year,his average income per month is (in $Rs.$)