Current Affairs 7th Class

Category : 7th Class

Data Handling

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.

Terms Related to Data

• Data: It 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.
• Secondary data: Secondary data is data that have been collected by others and used by other observer.
• Raw data: It is the original form of the data.
• Frequency: The number of times a particular observation occurs in a data is called frequency.
• Range: The difference between maximum and minimum value of the observation is called range.
• Class Interval: The interval in which variates lies is called class interval.
• Class Mark. = \[\frac{1}{2}\](lower limit + upper limit)

Example:

The runs scored by 11 members of a cricket team are as follows.

34, 0, 25, 34, 67, 73, 67, 1, 0, 34, 71.

Arrange the above data using tally marks.

Solution:

Example: The total sales of a company (in crores) in different years are as follows.

Present the above data in the form of a bar graph.

Solution:

Mean

Mean is defined as the ratio of sum of observations to total number of observations.

\[Mean=\frac{Sum\,of\,observations}{Total\,number\,of\,observations}\]

Example:

Find the mean of first five even natural numbers.

Solution: First five even natural numbers are 2, 4, 6, 8,10

From the above formula, we get

Mean\[=\frac{2+4+6+8+10}{5}=\frac{30}{5}=6\]