Question

Mean of 50 observations was found to be 80.4 but later on, it was discovered that 96 was misread as 69 at one place. Find correct mean

SUPER URGENT!!!!

Answer 1

Let the fiftieth observation be 69 and sum of the rest of the observations be S.
Then (S+69)=(80.4)50=4020.
But (S+96)=4047.
Then new mean is $\frac{S+96}{50}=80.94$.

Answer 2

Sum of all 50 observations = mean * no of observation = 80.4x 50 = 4020 now according to question 96 was misread by 69 So the new sum of observation = 4020 - 69 + 96 = 4020 + 27 = 40.47 now new mean = 4047/50 = 80.94 answer