Question

Calculate the arithmetic mean for the following data

x 11 12 13 14 15
f 25 7| 4 2​

Answer 1

Answer:

(a) RangeThe measure of dispersion which is easiest to understand and easiest to

calculate is the range. Range is defined as:

Range = Largest observation – Smallest observation

(b) Mean Deviation

(i) Mean deviation for ungrouped data:

For n observation x1

, x2

, ..., xn

, the mean deviation about their mean x is

given by