Question

mean of 50 observation was found to be 80.4. but later on it was discovered that 96 was misreed as 69 at one place .find the correct mean

Answer 1

Mean=sum of total number of observations /total number of observations
80.4=sum of total number of observation /50
sum of total number observations =4020
Now 96 was misread as 69
Therefore
corrected sum of total number observation
=4020-69+96
=4047
Corrected mean =4047/50
=80.94

Answer 2

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