Question

The mean of 40 observations was 160. It was detected on re-checking that the value 165 was wrongly copied as 125 for computation of mean. Find the correct mean​

Answer 1

Answer:

136

Step-by-step explanation:

let the sum of all observations be x then

x /40 = 160 [given]

x = 160*40

x = 6400

since a value 165 was copied as 125 ... difference between both of them = 165-125 = 40

so x + 40 will be the final sum of observation

(x+40) = 6400+40

then the mean will be :

(x+40)/40 = 6440/40

(x+40)/40 = 136