For a normal distribution,which of the following relations holds true?

If $\text{mean} = (3 \text{median} - \text{mode}) k$,then the value of $k$ is

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

The mode of the following frequency distribution is:

Class	$0-5$	$5-10$	$10-15$	$15-20$	$20-25$	$25-30$
Frequency $(f_i)$	$3$	$4$	$7$	$11$	$2$	$5$

Karl Pearson's coefficient of skewness of a distribution is $0.32$. Its standard deviation $(S.D.)$ is $6.5$ and the mean is $39.6$. The median of the distribution is:

Consider the following frequency distribution:

Class	$0-6$	$6-12$	$12-18$	$18-24$	$24-30$
Frequency	$a$	$b$	$12$	$9$	$5$

If $\text{mean} = \frac{309}{22}$ and $\text{median} = 14$,then the value of $(a-b)^{2}$ is equal to $.....$