Poor in maths
Number Theory
Level
2
All the students of a class performed poorly in Mathematics. The teacher decided to give grace marks of 10 to each of the students. Which of the following statistical measures will not change even after the grace marks were given?
Variance
mean
median
mode
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1 solution
Adding a constant value, c, to a random variable does not change the variance, because the mean increases by the same amount.
V a r ( x ) = n i = 1 ∑ n ( x i − σ ) 2 where σ is Mean of the distribution.