Classes or Class Intervals

Introduction|| Collection OF Data||Primary and Secondary Data|| classes|| Class interval|| Class size ( range )|| Presentation OF Group data & Single data ( ungrouped data )||Tally mark||Frequency distribution table

Unequal Class Intervals

A grouped frequency distribution table is given below with class mark (mid values of class intervals) and frequencies. Find the class intervals.

Class mark of class interval 60–70 is

The middle point of a class is m and the length of each class is 6 , then calculate the upper limit of the class of the class interval.

The middle point of a class is 10 and the length of each class is 12 , then calculate the lower limit of the class of the class interval.

The middle point of a class is 24 and the length of each class is 10 , then calculate the upper and lower limit of the class of the class interval.

Use the table given below to find : (a) The actual class limits of the fourth class. (b) The class boundaries of the sixth class. (c) The class mark of the third class. (d) The upper and lower limits of the fifth class. (e) The size of the third class. {:("Class interval","Frequency"),(30-34,7),(35-39,10),(40-44,12),(45-49,13),(50-54,8),(55-59,4):}

The fourth class interval for a grouped data whose first and second class intervals are 10 -15 and 15 -20 respectively is _________