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The sum of deviations of n numbers from 10 and 20 are p and q respectively. If (p-q)^2=10000 , then what is the value of n ?

Options

  1. A10
  2. B20
  3. C50
  4. D100

Correct answer

A. 10

Step-by-step solution

aligned & Since, ( x _ i -10 )= P & and ( x _ i -20 )= q & x _ i -10 n = P & x _ i -20 n = q aligned Now, (-10 n +20 n )^2=10000 100 n ^2=10000 n =10

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