Question

The mean of 150 items was found to be 60. later on it was discovered that the values of two values were misread , 52 and 8 instead of 152 and 88 respectively. find the correct mean

Answer 1

Hello Friend,

No of items= 150
Incorrect Mean= 60
Mean= Sum of Observation/No of observation
60= Sum/150
60*150= Sum
9000= Sum
New Sum= Incorrect Sum- Incorrect value+ Correct Value
New Sum= 9000-(52+88)+(152+88)
New Sum= 9000-140+240
New Sum= 9000+100
New Sum = 9100
Correct Mean= New Sum/Number of observation
Correct Mean= 9100/150
Correct Mean=60.67
Hope it helps

Answer 2

Answer:

mean equal to observa tion upon mean

ok