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NTA Abhyas JEE Main2020MathematicsStatisticsPractice

All the students of a class performed poorly in physics. The teacher decided to give grace marks of 15 to the entire class. Which of the following statistical measures will not change even after the grace marks were given?

Options

  1. Amedian
  2. Bmode
  3. Cvariance
  4. Dmean

Correct answer

C. variance

Step-by-step solution

Variance is not changed by the change of origin. σ = ∑ x - x - 2 n . Therefore, y = x + 15 ⇒ y - = x - + 15 σ 1 = ∑ y + 15 - y - - 15 2 n = ∑ y - y - 2 n = σ .

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