Life of bulbs produced by two factories A and B are given below:


The bulbs of which factory are more consistent from the point of view of the length of life?

For Factory A



Now, N=120,


Mean






Variance = 12097


Standard Deviation


SD = 109.98


Coefficients variation =


Cv=13.61


For Factory B



Now, N=120,


Mean






Variance = 11400


Standard Deviation


SD = 106.77


Coefficients variation =


Cv=14.29


Since, the coefficient of variation of factory B is greater than the coefficient of variation of factory A,


Hence, This means bulbs of factory A are more consistent from the point of view of the length of life.


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