Find the mode of the following array of an individual series of scores 7,10, 12, 12, 12, 11, 13, 13, 17.

∴ Mode is 12 

(ii) Uses of Mode : Mode is the average to be used to find the ideal size, e.g., in business forecasting, in manufacture of ready-made garments, shoes etc. 

(c) Empirical Relation between Mode, Median & Mean : Mode = 3 Median - 2 Mean 

RANGE 

The range is the difference between the highest and lowest scores of a distribution. It is the simplest measure of dispersion. It gives a rough idea of dispersion. This measure is useful for ungrouped data. 

(a) Coefficient of the Range : If l and h are the lowest and highest scores in a distribution then the coefficient of the Range = (h - l)/(h + l).