Nine friends have a dinner in a hotel. Eight of them spent $Rs.\, 12$ each on their meals and the ninth spent $Rs. \,16$ more than the average expenditure of all the nine. Find out the total money in $Rs.$ spent by them?

The average of a collection of $20$ measurements was calculated to be $56\, cm .$ But later, it was found that a mistake had occurred in one of the measurements which was recorded as $64 \,cm ,$ but should have been $61 \,cm$. The correct average must be? (in $cm$)

Average age of $A, B$ and $C$ is $84\, years.$ When $D$ joins them the average age becomes $80\, years.$ A new person, $E,$ whose age is $4 \,years$ more than $D,$ replaces $A$ and the average of $B, C, D$ and $E$ becomes $78\, years.$ What is the age of $A$ ? (in $years$)

The average weight of all the $11$ players of Indian cricket team is $50\, kg.$ If the average of first six lightest weight players is $49\, kg$ and that of the six heaviest players is $52\, kg$. The average weight of the player which lies in the sixth position in the list of players when all the $11$ $players$ are arranged in the order of $increasing$ or $decreasing$ $weights$ (in $kg$)

The average of runs scored by a cricketer in his $99$ innings is $99.$ How many runs will he have to score in his $100^{\text {th }}$ innings so that his average of runs in $100$ innings may be $100 ?$