Find the value of p for the following frequency distribution whose mean is 16.6.


X



8



12



15



P



20



25



30



F



12



16



20



24



16



8



4



xi



fi



xi×fi



8



12



96



12



16



192



15



20



300



P



24



24P



20



16



320



25



8



200



30



4



120




∑fi = 100



∑xi×fi = 1228 + 24P



By putting the formula of mean we get;


Mean = = 16.6 (given)



16.6×100 = 1228 + 24P



1660 = 1228 + 24P


24P = 1660-1228


24P = 432



So, the value of P is 18.


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