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If the mean deviation about the median of the numbers a , 2 a , , 50 a is 50 , then | a | equals

Options

  1. A3
  2. B4
  3. C5
  4. D2

Correct answer

B. 4

Step-by-step solution

1 n | x _ i - A | A = Median = 25 a +26 a 2 =25.5 a Mean deviation = 1 50 | a -25.5 a |+|2 a -25.5 a | = 2 50 (24.5 a +23.5 a )+ (0.5 a ) = 2 50 312.5 a =50 (Given) 625 a =2500 a =4

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