NTA Abhyas JEE Main2020MathematicsStatisticsPractice

If the variance of the first 50 odd natural numbers is V 1 and the variance of next 50 odd natural numbers is V 2 , then V 1 + V 2 is equal to

Correct answer

1666

Step-by-step solution

Note that V 1 = V 2 (Variance is independent of shifting of orgin) Now V 1 = 1 2 + 3 2 + … + 99 2 50 - 1 + 3 + . . + 99 50 2 = 1 50 50 × 101 × 99 3 - 2500 = 3333 - 2500 = 833 Hence, V 1 + V 2 = 1666

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