The mean of the first ten natural numbers is ........

In a maths test taken by $40$ students,the average score of $30$ boys is $16$ and the average score of $10$ girls is $12$. Which of the following gives the average score of the whole class?

Daily wages of $110$ workers,obtained in a survey,are tabulated below:

Daily wages (in $Rs.$)	Number of workers
$100-120$	$10$
$120-140$	$15$
$140-160$	$20$
$160-180$	$22$
$180-200$	$18$
$200-220$	$12$
$220-240$	$13$

Compute the mean daily wages of these workers (in $Rs.$).

For a given frequency distribution,$\Sigma f_{i} x_{i} = 1790$ and $\Sigma f_{i} = 50$. Then,the mean $\bar{x} = $ ..........

The mean of the following data is $16.$ Find the missing frequency $f.$

Class	$0-4$	$4-8$	$8-12$	$12-16$	$16-20$	$20-24$	$24-28$	$28-32$	$32-36$
Frequency	$6$	$8$	$17$	$23$	$16$	$15$	$f$	$4$	$3$

The mean of $15$ observations is $16$. If $2$ is added to each observation and then each result is divided by $3$,the new mean is: