What is the relationship between mean,median,and mode for a moderately skewed distribution?

What is the relation between the mean and the median of a discrete data set?

The sum of the absolute deviations is minimum when taken with respect to:

Let $a_1, a_2, \dots, a_{101}$ be a group of real numbers such that $a_i > a_{i+1}$ for all values of $i$ and the mean square deviation of the group is minimum about the number $a_{51}$. Then the mode of the group will be:

$A$ set of numbers consists of three $4$'s,five $5$'s,six $6$'s,eight $8$'s,and seven $10$'s. The mode of this set of numbers is:

If $\text{Mean} = x(3 \times \text{Median} - \text{Mode})$,then what is the value of $x$?