There were $35$ students in a hostel. If the number of students is increased by $7,$ the expenditure on food increase by $Rs. \,42$ per $day$ while the average expenditure of students is reduced by $Rs.\, 1.$ What was the initial expenditure on food per day? (in $Rs.$)

The batting aterage for $40$ innings of a cricketer is $50$ nuns. His highest score exceeds his lowest score by $172$ runs. If these two innings are excluded, the average of the remaining $38$ innings is $48$ runs. The highest score of the player is

$16$ children are to be divided into two groups $A$ and $B$ of $10$ and $6$ children, respectively. The average marks obtained by the children of group $A$ is $75$ and that of all the children is $76 .$ Then, the average marks of the children of group $B$ is ?

The average weight of $3$ men $A, B$ and $C$ is $84 \,k g .$ Another man, $D,$ joins the group, and the average weight becomes $80\, kg .$ If another man, $E$, whose weight is $3 \,kg$ more than that of $D ,$ replaces $A$, then average weight of $B , C , D$ and $E$ becomes $79 \,kg$. The weight of $A$ is (in $kg$)

In an examination average marks obtained by the girls of a class is $85$ and the average marks obtained by the boys of the same class is $87 .$ If the girls and boys are in the ratio $4: 5,$ average marks of the whole class $(approx.)$ is closest to