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For 20 observations the mean is 10 and the variance is 4 (divisor n). Later one observation 8 is found to be wrong and is replaced by 12. What is the correct variance?

Competition practiceStatistics
  • A8
  • B3.96
  • C4
  • D1.99

Step-by-Step Solution

. New , new . Variance .
Answer: B) 3.96

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