The average age of a cricket team reduces by $2$ when two senior players aged $32$ and $30$ are replaced by $2$ youngsters of equal age. What is the age of these youngsters?

Find the average of first $25$ multiples of $5$.

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 $100$?

Out of four numbers,the average of the first three is $16$ and that of the last three is $15$. If the last number is $20$,then the first number is:

The mean of the marks obtained by $100$ students is $60$. If the marks obtained by one of the students was incorrectly calculated as $75$ whereas the actual marks obtained by him were $65$,what is the correct mean of the marks obtained by the students?

$A$ 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?