NTA Abhyas JEE Main2020MathematicsStatisticsPractice

The median of a set of 9 distinct observations is 20.5 . If each of the largest 4 observations of the set is increased by 4 , then the median of the new set

Options

Ais increased by 4
Bis decreased by 4
Cis two times the original median
Dremains the same as that of the original set

Correct answer

D. remains the same as that of the original set

Step-by-step solution

If x 1 , x 2 , x 3 … , x 9 are the observations such that, x i + 1 ≥ x i i ∈ 1,2 , … 8 Median = x 5 ∵ x 6 , x 7 , x 8 , x 9 are increased by 4 hence, median x 5 remains the same.

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