The mean of $10$ observations is $15.7$. If a new observation $19$ is included,the new mean is ..........

The following are the ages of $300$ patients getting medical treatment in a hospital on a particular day:

Age (in years)	$10-20$	$20-30$	$30-40$	$40-50$	$50-60$	$60-70$
Number of patients	$60$	$42$	$55$	$70$	$53$	$20$

Form:
$(i)$ Less than type cumulative frequency distribution.
$(ii)$ More than type cumulative frequency distribution.

If $Z=12$ and $M=16,$ then $\bar{x}=$ ............

Find the mean,median and mode of the following frequency distribution:

Class	$0-50$	$50-100$	$100-150$	$150-200$	$200-250$	$250-300$	$300-350$
Frequency	$10$	$15$	$30$	$20$	$15$	$8$	$2$

The mileage $(km/l)$ of $50$ cars of the same model was tested by a manufacturer and details are tabulated as given below:

Mileage $(km/l)$	$10-12$	$12-14$	$14-16$	$16-18$
Number of cars	$7$	$12$	$18$	$13$

Find the mean mileage.
The manufacturer claimed that the mileage of the model was $16 \, km/l$. Do you agree with this claim?

The excluding type of class $30-45$ does not include .........