The monthly consumption of electricity (in units) of some families of a locality is given in the following frequency distribution:


Monthly consumption (in units)



140 - 160



160 - 180



180 - 200



200 - 220



220 - 240



240 - 260



260 - 280



Number of families



3



8



15



40



50



30



10



Prepare a 'more than type' ogive for the given frequency distribution.

The frequency distribution table for ‘more than’ type is:


HEIGHT(cm)



CUMULATIVE FREQUENCY (Cf)



more than 140



153 + 3 = 156



more than 160



145 + 8 = 153



more than 180



130 + 15 = 145



more than 200



90 + 40 = 130



more than 220



40 + 50 = 90



more than 240



10 + 30 = 40



more than 260



10



Lets plot a graph of ‘more than’ ogive, taking lower limits of the class intervals on x - axis and cumulative frequencies on y - axis.



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