The following table gives the scores of two groups of students, Group A and Group B. Which group shows greater consistency in performance? - Group A: Mean $\bar{x}_A = 65$, Standard Deviation $\sigma_A = 13$ - Group B: Mean $\bar{x}_B = 72$, Standard Deviation $\sigma_B = 18$

Calculate the Range, Coefficient of Range, Quartile Deviation ($QD$), and Coefficient of Quartile Deviation for the following discrete data: Data ($x$): $12, 18, 25, 32, 40, 48, 55, 63, 70, 78, 85$.

Calculate the Standard Deviation ($\sigma$) and Coefficient of Variation ($CV$) for the following frequency distribution: $$\begin{array}{|c|c|c|c|c|c|} \hline \text{Marks } (x) & 10 & 20 & 30 & 40 & 50 \\ \hline \text{Frequency } (f) & 3 & 7 & 12 & 6 & 2 \\ \hline \end{array}$$