The following cumulative frequency distribution table shows the daily electricity consumption (in KV) of 40 factories in an industrial state:


Consumption (in KV)



No. of Factories



Below 240


Below 270


Below 300


Below 330


Below 360


Below 390


Below 420



1


4


8


24


33


38


40



(i) Represent this as a frequency distribution table.


(ii) Prepare a cumulative frequency table.


Consumption (Kw)



No. of factories



Class interval



Frequency



Below 240



1



0-240



1



Below 270



4



240-270



3



Below 300



8



270-300



4



Below 330



24



300-330



16



Below 360



33



330-360



9



Below 390



38



360-390



5



Below 420



40



390-420



2



(ii)


Class interval



Frequency



Consumption (in Kw)



No. of factories



0-240



1



More than 0



40



240-270



3



More than 240



39



270-300



4



More than 270



36



300-330



16



More than 300



32



330-360



9



More than 330



16



360-390



5



More than 360



7



390-420



2



More than 390



2





More than 420



0




N = 40





8