What was the average daily expenditure in $Rs.$ of a man in $1999$ who spent $Rs. \, 76535$ in the first half of the year and $Rs. \, 88165$ in the second half?

The mean of $19$ observations is $4$. If one more observation of $24$ is added to the data,the new mean will be

There was one mess for $30$ boarders in a certain hostel. On the number of boarders being increased by $10,$ the expenses of the mess were increased by $Rs.\, 40$ per month while the average expenditure per head diminished by $Rs.\, 2.$ Find out the actual monthly expenses (in $Rs.$).

$12 \%$ of Kaushal's monthly salary is equal to $16 \%$ of Nandini's monthly salary. Suresh's monthly salary is half that of Nandini's monthly salary. If Suresh's annual salary is $Rs.\, 1.08$ lakhs,what is Kaushal's monthly salary in $Rs.$?

$A$ batsman has a certain average of runs for $12$ innings. In the $13^{th}$ innings,he scores $96$ runs,thereby increasing his average by $5$ runs. What is his average after the $13^{th}$ innings?

There are two groups $A$ and $B$ of a class,consisting of $42$ and $28$ students,respectively. If the average weight of group $A$ is $25 \, kg$ and that of group $B$ is $40 \, kg$,find the average weight of the whole class.