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The mean of 20 observations was 45. One observation was taken as 65 by mistake, and after correcting it the mean became 44. What was the correct value of that observation?

Competition practiceStatistics
  • A85
  • B44
  • C55
  • D45

Step-by-Step Solution

The total fell from 900 to 880, i.e. by 20. So the correct value is .
Answer: D) 45

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