$A$ man spends $Rs. 1800$ monthly on an average for the first four months and $Rs. 2000$ monthly for the next eight months and saves $Rs. 5600$ a year. His average monthly income is (in $Rs.$)

The batting average for $40$ innings of a cricket player is $50$ runs. 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

The average weight of five persons sitting in a boat is $38\, kg$. The average weight of the boat and the persons sitting in the boat is $52\, kg$. What is the weight of the boat (in $kg$)?

An aeroplane travels $2500 \, km$,$1200 \, km$,and $500 \, km$ at $500 \, km/h$,$400 \, km/h$,and $250 \, km/h$ respectively. The average speed is (in $km/h$):

If the difference between the average of $x, y$ and $y, z$ is $12,$ then the difference between $x$ and $z$ is

$A$ 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?