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| Introduction |
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| Man has the skill of communication by which he is able to convince others about his point of view. Today graphics, tables, reasoning, estimation and prediction are playing a very important role in stating the facts in terms of figures. |
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| Statistics deals mainly in communicating facts and figures in terms of a method called statistical method. Collection, classification, tabulation, representation, reasoning, testing and drawing inferences are part of statistical methods. |
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| Rainfall patterns of a particular city over a period of time can be analyzed and a fair estimate about next season can be arrived at, with the help of figures (data) collected over a period of time. |
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| The word statistics is used with two meanings. |
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 Systematically collected and presented numerical data. |
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 Processing the numerical data and to draw conclusions from there. |
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| The following figure shows some information about population. Observe the figure and try to answer the questions below it. |
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 What information about population does the figure show? |
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 State the time interval in which the information has been collected . |
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 In how many parts is the time interval divided? How many years does each part contain? |
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 Does the figure show that the birth rate is constantly declining? |
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 Does the figure show a constantly declining death rate? |
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 State the census year which shows the maximum birth rate. How much is it? |
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 State the time interval in which the death rate has fallen suddenly. |
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| From these questions, we know that the figure contains a variety of useful information. Also, it is easily comprehendable. |
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| To collect such information using proper methods and to draw conclusions from it, has now become an independent subject, called statistics. The information collected is mainly in the form of numbers. |
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| Today, statistics has become a part of all branches of knowledge. It is used to study problems in Biology, Psychology, Economics, Sociology, Trade, Industry etc., |
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| The statistical method of studying a problem broadly consists of the following steps: |
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 to collect numerical data about the problem, |
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 to present the collected data systematically, |
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 to analyse the data and |
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 to interpret the data and draw conclusions from it. |
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