Chapter 5



After completing this chapter, you can understand the following:

  • The definition, meaning and significance of dispersion.
  • The calculation of different dispersions such as range, quartiles, quartile deviation, standard deviation [SD] and coefficient of variation [CV].
  • Managerial applications using SD and CV.
  • How these measures can be used to make decisions related to biological studies?

An average gives a single value that is considered to be representative of the whole group, but it is not going to reveal how the items in the groups are scattered or spread.


Six boys having the marks 100, 100, 100, 0, 0 and 0; another group of six boys have the marks as 50, 60, 50, 50, 40 and 50. Both ...

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