Q74.The mean and the variance of five observations are 4 and 5.20, respectively. If three of the observations are 3, 4 and 4; then the absolute value of the difference of the other two observations, is : (1) 3 (2) 5 (3) 7 (4) 1
What This Question Tests
The question tests the ability to use the definitions of mean and variance for a set of observations to find unknown values and their difference.
Concepts Tested
Formulas Used
Mean = (Σxi)/n
Variance = (Σxi²)/n - (Mean)²
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Statistics
- Topic
- Mean and variance of grouped data
- Year
- 2019
- Shift
- 12 Jan Shift 2
- Q Number
- Q74
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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