﻿ Definition and examples class interval | define class interval - algebra 1 - Free Math Dictionary Online

# Class Interval

## Definition of Class Interval

While arranging large amount of data (in statistics), they are grouped into different classes to get an idea of the distribution, and the range of such class of data is called the Class Interval.

• Class intervals are generally equal in width and are mutually exclusive.
• The ends of a class interval are called class limits, and the middle of an interval is called a class mark.

• Class interval is generally used to draw histogram.

### Example of Class Interval

In the table above, heights of 20 students of a class are divided into classes with the size of each class interval being 5.

A. 426 - 443
B. 335 - 351
C. 318 - 438
D. 336 - 353

### Solution:

Step 1: Range of the data = higher value - lower value = 438 - 318 = 120
Step 2: Width = Range/number of classes = 120/7 = 17.14 ˜ 18
[Round to the higher value.]
Step 3: Construct the class limits (weight gains) with width 18, so that the least and the highest values are included.
Step 4: The class limits, boundaries, tally marks and the frequency for each class (number of tally marks) are shown in the table.
Step 5:

Step 6: The class interval in which the weight increase maximum is 336 - 353. [Frequency is more for the class 336 - 353.]

Translate :

Please provide your email for a free trial as a Teacher or Student. This trial will be valid for the current academic year (2015-16). An email to this address includes the password to login to the full web application. You will also receive other promotional emails as and when such deals become available.

I am a Teacher Student