Q75.In a set of 2n observations, half of them are equal to ' a ' and the remaining hall are equal to ' −a′ '. If the standard deviation of all the observations is 2 ; then the value of |a| is : (1) 2 (2) √2 (3) 4 (4) 2√2
What This Question Tests
This question tests the application of the formula for standard deviation for a simple set of observations, requiring calculation of the mean first.
Concepts Tested
Formulas Used
Standard deviation σ = √(Σ(xi - μ)² / N)
Mean μ = Σxi / N
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📋 Question Details
- Chapter
- Statistics
- Topic
- Standard Deviation
- Year
- 2013
- Shift
- 25 Apr Online
- Q Number
- Q75
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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