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NTA Abhyas 2020
Exam
NTA Abhyas
Year
2020
Subject
Mathematics
Chapter
Statistics

NTA Abhyas 2020 · Mathematics · Statistics

The arithmetic mean of a set of 50 numbers is 38. If two numbers of...

The arithmetic mean of a set of 5050 numbers is 38.38. If two numbers of the set, namely 6060 and 4040 are discarded, the arithmetic mean of the remaining set of numbers is

Options

  1. A38.538.5
  2. B37.537.5
  3. C36.536.5
  4. D3636

Correct answer

B. 37.537.5

Step-by-step solution

Given Σxi50=38,Σxi=1900\dfrac{Σ{x}_{i}}{50} = 38, Σ{x}_{i} = 1900
New value of Σxi=1900−60−40=1800,n=48Σ{x}_{i} = 1900 - 60 - 40 = 1800, n = 48
New mean =180048=37.5= \dfrac{1800}{48} = 37.5
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