For a given frequency distribution,$n=200$,$\Sigma f_{i} d_{i}=0$ and $A=25$. Then,$\bar{x}=\ldots \ldots \ldots \ldots$

Is it true to say that the mean,mode,and median of grouped data will always be different? Justify your answer.

Find the median of the following frequency distribution:

Class	$60-70$	$70-80$	$80-90$	$90-100$	$100-110$	$110-120$
Frequency	$5$	$15$	$20$	$30$	$20$	$8$

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	$10$	$15$	$30$	$20$	$15$	$8$	$2$

In a frequency distribution,the modal class is $70-85$ with frequency $25$. The frequencies of the classes succeeding and preceding the modal class are $20$ and $8$ respectively. Then,the values of $f_{0}, f_{1}$ and $f_{2}$ are respectively.

The formula to find the mean of a grouped data by the direct method is .........