Question

arithmetic mean of 50 items is 104. While checking, it was noticed that observation 98 was misread as 89.find the correct value of mean​

Answer 1

sum of 20 numbers/20 = 50

sum of 20 numbers =1000

sum of 20 numbers - incorrect no.+ correct no.= 1000-44+64= 1020

mean = 1020/20 = 51

Answer 2

Answer:

The correct value of mean = 104.18

Explanation:

Given that Arithmetic mean of 50 items = 104    

after checking, noticed that 98 was misread as 89

Here  we need to find correct mean  

from data Arithmetic mean of 50 items  = 104

sum of the 50 items = mean × 50 = 104 × 50 = 5200

98 was misread as 89 ⇒ add 98 to 5200 and subtract 89

                                      ⇒  5200 + 98 - 89

                                      ⇒  5,209

the correct mean =  5209 ÷ 50 = 104.18