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The mean of the data set comprising of 16 observations is 16. If one of the observation valued 16 is deleted and three new observations valued 3, 4 and 5 are added to the data, then the mean of the resultant data, is:
- 15.8
- 14.0
- 16.8
- 16.0
Correct answer: 14.0
Solution
Original sum = 16 x 16 = 256. After deleting one 16: sum = 240 over 15 values. Adding 3, 4, 5: sum = 252 over 18 values, so the new mean = 252/18 = 14.0.
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