If
, then
=
We have given,
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Also,
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Putting this in above equation
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Now, given
…[1]
using this
We have,
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…[2]
We know,
If x1, x2, … , xn are observations with frequencies f1, f2, … , fn i.e. x1 occurs f1 times and x2 occurs f2 times and so on, then mean(
) of observations is given by
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From [1] and [2]
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