Saved Bookmarks
| 1. |
What is the effect on finding mean of 20 scores if one of them is copied as 73 for 37 wrongly |
|
Answer» We have to find the EFFECT on finding MEAN of 20 scores if one of them is copied as 73 for 37 wrongly. solution : one of the observations is copied as 73 for 37 wrongly. so the true value of the observation is 37. true mean = (sum of 19 observations + 37)/20 and false value of the observation is 73. so false mean = (sum of 19 observations + 73)/20 so the effect on finding means = false mean - true mean = (sum of 19 observations + 73)/20 - (sum of 19 observations + 37)/20 = (73 - 37)/20 = 36/20 = 1.8 hence, if m is mean of 20 observations, after mistake, it will be (m + 1.8) THEREFORE mean of 20 scores if one of them is copied as 73 for 37 wrongly , is increased by 1.8 also read similar QUESTIONS : The mean or 20 observations was 60. It was detected on rechecking that the value of 125 wrongly copied as 25 for computa... in a class test, the mean marks scored by a class of 40 students was calculated as 18.2. later on, it was detected that ... |
|