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If the mean deviation of number 1,1+d, 1+2 d, ., 1+100 d from their mean is 255 , then the d is equal to

Options

  1. A10.0
  2. B20.0
  3. C10.1
  4. D20.2

Correct answer

C. 10.1

Step-by-step solution

aligned & Mean ( x )= sum of quantities n = n 2 (a+1) n = 1 2 [1+1+100 d]=1+50 d & M.D. = 1 n |x_i- x | 255= 1 101 [50 d+49 d+48 d+ .+d+0+d+ +50 d]= 2 d 101 [ 50 51 2 ] & d= 255 101 50 51 =10.1 aligned

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