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Chapter 21 – Data Handling – R S Aggarwal Solutions for class 8
Some definitions:
Data: It is the systematic record of numerical facts of a specific type of information.
Raw data: Randomly collected information is called raw data. It is the collection of initially gathered observations
Range: It is the difference between the highest and the lowest value of the observation.
Statistics: It is the branch of mathematics which deals with the collection, presentation, analysis and interpretation of the numerical data.
Frequency of an observation: It means the number of times a particular observation occurs in a given data.
Frequency distribution: Representation of data in tabular form showing the frequency of each observation.
Tally marks: They are a form of numeral used for counting. It is a good way of keeping track of numbers in groups of five. We represent | | | | for counting 4 numbers and | | | | for counting 5 numbers.
