The average of $50$ numbers is $30.$ If two numbers, $35$ and $40$ are discarded, then the average of the remaining numbers is nearly.
$28.32$
$28.78$
$29.27$
$29.68$
The mean of $100$ items was $46 .$ Later on, it was discovered that an item $16$ was misread as $61$ and another item $43$ was misread as $34.$ It was also found that the number of items was $90$ and not $100 .$ Then, what is the correct mean?
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 mean weight of $34$ students of a school is $42 \,kg$. If the weight of the teacher be included, the mean rises by $400 \,g$. Find the weight of the teacher (in $kg$).
The average salary, per head, of all the workers of an institution is $Rs.\, 60 .$ The average salary of $12$ officers is $Rs.\, 400$; the average salary, per head, of the rest is $Rs.\,56.$ The total number of workers in the institution is
Three year ago, the average age of a family of five members was $27 \,year.$ The present average age is also $27 \,year$ after the inclusion of a child into the family. Find the age of the child in $year$ ?