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Rohit found the mean of 20 numbers to be 32. He then noticed that he had copied one number as 72 instead of 27, and had also missed out a 21st number. After both corrections the mean of the 21 numbers is 30. What is the missed number?

Competition practiceStatistics
  • A35
  • B33
  • C30
  • D45

Step-by-Step Solution

Corrected sum of 20 . Sum of 21 . Missed number .
Answer: A) 35

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