The average salary of $20$ workers in an office is $Rs. \,1900$ per $month.$ If the manager's salary is added, the average becomes $Rs. \,2000$ per $month.$ The manager's annual salary (in $Rs.$) is
$24000$
$25200$
$45600$
$48000$
The average weight of $21$ boys was recorded as $64 \,kg.$ If the weight of the teacher was added, the average increased by one $kg.$ What was the teacher's weight?
The average height of the students of a class of $20$ is $105\, cm$. If ten more students of average height of $120 \,cm$ join this class, the average height of the class will become (in $cm$)
The average of the first nine integral multiples of $3$ is
The average age of $80$ boys in a class is $15.$ The average age of a group of $15$ boys in the class is $16$ and the average age of another $25$ boys in the class is $14 .$ What is the average age of the remaining boys in the class ?
The average weight of $5$ persons, sitting in a boat, is $38 \,Kg$. If the average weight of the boat and the persons sitting in the boat is $52 \,Kg$, what is the weight of the boat? (in $kg$)