Question:
The mean of a data set consisting of 20 observations is 40. If one observation 53 was wrongly recorded as 33, then the correct mean will be :
The mean of a data set consisting of 20 observations is 40. If one observation 53 was wrongly recorded as 33, then the correct mean will be :
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Find the original sum from the mean and correct it by the difference 53 - 33.
Updated On: Oct 31, 2026
- 41
- 49
- 40.5
- 42.5
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The Correct Option is A
Solution and Explanation
Incorrect sum = \(20\times40=800\).
Correct sum = \(800-33+53=820\).
Correct mean = \(\frac{820}{20}=41\).
Answer: (1) 41
Correct sum = \(800-33+53=820\).
Correct mean = \(\frac{820}{20}=41\).
Answer: (1) 41
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