The mean of 150 items was found to be 60. Later on, it was discovered that the values of two items were misread as 52 and 8 instead of 152 and 88 respectively.
Question:
The mean of 150 items was found to be 60. Later on, it was discovered that the values of two items were misread as 52 and 8 instead of 152 and 88 respectively. Find the correct men.
Solution:
Mean of 150 items = 60
Sum of 150 items $=(150 \times 60)=9000$
New sum $=[9000-(52+8)+(152+88)]=9180$
Correct mean $=\frac{\text { New sum }}{\text { Total items }}=\frac{9180}{150}=61.2$
Therefore, the correct mean is $61.2$.