Mean of 50 observations was found to be 80.4. -Maths 9th

Mean of 50 observations was found to be 80.4. -Maths 9th
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Answer :

Here, n = 50,  x̅ = 80.4  So,  x̅ = ∑ xi/n  ⇒  80.4 =  ∑ xi/50 ⇒  ∑ xi = 80.4 x 50 = 4020 Correct value of  ∑ xi = 4020 - 69 + 96 = 4047 Correct mean = Correct value of  ∑ xi/n = 4047/50 = 80.94
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