A batsman scores $87$ runs in the $21^{st}$ match of his career. His average runs per match increase by $2.$ What is his average before the $21^{st}$ match?
$45$
$46$
$44$
$43$
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 $100 ?$
What was the average in $Rs.$ daily expenditure of a man in $1999$ who spent $Rs. \,6535$ in the first half year and $Rs.\, 88165$ in the last?
The average salary of the entire staff in a office is $Rs.\, 120$ per $month.$ The average salary of officers is $Rs.\, 460$ and that of non-officers is $Rs. \,$ $110 .$ If the number of officers is $15,$ then find the number of non-officers in the office ?
The average age of four brothers is $12 \,year.$ If the age of their mother be also included, the average is increased by $5\, year.$ The age of the mother (in $years$) is
The average age of $30$ women decreases by $3$ $months$ if a new person Neha is included in place of a $25\, year$ old woman. Calculate the age of Neha in $year$ ?