Page 4 - 7-Math-13 INFORMATION HANDLING

113.. IQnufoarmdartaiotnicHaEnqdulinagtions eeLLeeaarrnn..PPuunnjjaabb

version: 1.1 13.1.2 Frequency Distribution

The conversion of ungrouped data into grouped data so that the
frequencies of different groups can be visualized is called frequency
distribution

The table which shows the frequency of class intervals is called
the frequency table.

• Frequency
The number of values that occurs in a group of a data is called its
frequency, e.g. in the above given example,

The frequency of (11 - 40) is 5.
The frequency of (41 - 70) is 7.
The frequency of (71 - 100) is 8.
• Class Limits
Upper Class Limit: The greatest value of a class interval is called the
upper class limit, e.g. in the class interval (41 - 70), 70 is the upper
class limit.
Lower Class Limit: The smallest value of a class interval is called the
lower class limit, e.g. in the class interval (71 - 100), 71 is the lower
class limit
• Class Intervals
Each group of a data is also known as the class interval. For example,
(11 - 40), (41 - 70) and (71 - 100) are class intervals. Each interval
represents all the values of a group.
Size of the Class Interval: The number of values in a class interval
is called its size or length. For example, the size or length of class
interval (11 - 40) is 30 that can be checked by counting. It can also be
calculated by subtracting the lowest value of the data from greatest
value and divide the result by the number of class intervals as shown
below:
Lowest value = 11
Greatest value = 100
Now use the formula to calculate the size.

4