1 Answer
Solution :-
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\( Mean , \overline{X} = \dfrac{\displaystyle\sum_{i=1}^{7} f_i x_i}{N}\)
\( N= \displaystyle\sum_{i=1}^{n} f_i \)
\( \overline{X}\) = \( \dfrac{760}{40}\)
= 19
Now, Variance
\( σ^2=\dfrac{1}{N} \displaystyle\sum_{i=1}^{7} f_i (X_i-\overline {X} )^2\)
= \( \dfrac{1}{40}\times 1736\)
= 43.4
Answered by Abhisek | 1 year agoRelated Questions
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