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JEE Main202225 Jun 2022Evening ShiftMathematicsStatisticsActual

If the mean deviation about the mean of the numbers 1 , 2 , 3 , … … , n , where n is odd, is 5 n + 1 n , then n is equal to ______.

Correct answer

0

Step-by-step solution

We know that mean deviation about the mean of odd natural number is given by M.D  x = 1 n n 2 - 1 4 So, now 1 n n 2 - 1 4 = 5 n + 1 n (given) ⇒ n - 1 = 20 ⇒ n = 21

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