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The sum of deviations of n number of observations measured from 2.5 is 50. The sum of deviations of the same set of observations measured from 3.5 is -50. What is the value of n?

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  1. 50
  2. 60
  3. 80
  4. 100

Answer (Detailed Solution Below)

Option 4 : 100
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Detailed Solution

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Concept:

Deviation = |data value - mean|

Calculation:

Let, data value be 

 and 

Now,

-50 + 3.5n = 50 + 2.5n

⇒ n = 100

⇒ n = 100

Hence, option (4) is correct. 

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