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A teacher found the mean of 20 numbers to be 30. Later it was discovered that one number was wrongly read as 90 instead of the correct value 9.
Find the correct mean.

Class 9Measures of Central TendencyStatistics and Probability
  • A51.9
  • B22.95
  • C25.95
  • D28.95

Step-by-Step Solution

Wrong total = . Correct total = 600 - 90 + 9 = 519. Correct mean = .
Answer: C) 25.95

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