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प्रश्न
If the mean of frequency distribution is 8.1 and Σfixi = 132 + 5k, Σfi = 20, then k =?
विकल्प
3
4
5
6
उत्तर
6
Explanation:-
Given:
Σfixi = 132 + 5k, Σfi = 20 and mean = 8.1
Then,
Mean `=(sumf_ix_i)/(sumf_i)`
`8.1 = (132 +5k)/20`
162 = 132 + 5k
5k = 30
k = 6
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