7th Class Mathematics Data Handling Introduction

     Introduction

Modern society is information oriented. Every person wants numeric information of different fields of the society like the marks obtained in a particular subject by the students, five year plans etc. Statistics is a branch of Mathematics which deals with the process, analyzing and interpreting the data. Data is defined as the particular information in numeric form.  

      Primary Data

Primary data means the data that have been collected by collector for some purpose. It means when an authorized organization or an investigator or an enumerator collects the data for the use to himself or with the help or an institution or an expert then the data collected is called primary data.                              

      Secondary Data

Secondary data is data that have been collected by others and used by someone eIse. It means that after performing statistical operations of primary data the result become useful to others is called the secondary data.  

       Raw Data

Raw data (or ungrouped data) is the data which is not arranged in any particular fashion or pattern. It is the original form of the data. e.g. The height of 5 students in a class is 123 cm, 120 cm, 129 cm, 135 cm, 121 cm.  

      Grouped Data

Grouped data is the data which is arranged in classes or group to bring out salient mature of the group. Firstly it may arrange in ascending or descending order and then divide into groups.  

      Variable 

A measurable characteristic is called a variable or variate   eg. Age, height, income  

       Attribute

A non - measurable characteristic is called an attribute.  

       Frequency

The number of times a particular observation occurs in a data is called frequency. In other words, it is number of times an observation occurs, e.g in a data 1, 2, 3,4,5, 2, 1, 3, 2, 4, 6, 5, 2, 3, 2, 1, 2, 5. The frequency of 2 in the above data is 6 because it occurs 6 times in the observation.  

The run scored by 11 member of a cricket team are: 34, 0, 25, 34, 67, 73, 67,1, 0,71                

Represent the given data by using tally marks.                

Solution: