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JEE Main 20139 AprilOnline
Exam
JEE Main
Year
2013
Date
9 April
Mode
Online
Subject
Mathematics
Chapter
Statistics

JEE Main 2013 · 9 April · Online · Mathematics · Statistics

The mean of a data set consisting of 20 observations is 40 . If one...

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:

Options

  1. A41
  2. B49
  3. C40.540.5
  4. D42.542.5

Correct answer

A. 41

Step-by-step solution

 Correct mean =20×40−33+5520=\text{ Correct mean }=\frac{20 \times 40-33+55}{20}=41.1 Nearest option : (a) 41
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