The electricity bills (in rupees) of 40 houses in a locality are given below:

116, 127, 107, 100, 80, 82, 91, 101, 65, 95, 87, 81, 105, 129, 92, 75, 89, 78, 87, 81, 59, 52, 65, 101, 115, 108, 95, 65, 98, 62, 84, 76, 63, 128, 121, 61, 118, 108, 116, 130.


Construct a grouped frequency table.

Minimum data = 52


Maximum data = 130


Range = 130 – 52 = 78


Let the class size = 10


Number of classes = or 8 classes


Class



Frequency



52 – 62



2



62 – 72



6



72 – 82



6



82 – 92



6



92 – 102



7



102 – 112



4



112 – 122



5



122 – 132



4



11