Q67.The mean of 6 distinct observations is 6. 5 and their variance is 10. 25. If 4 out of 6 observations are 2, 4, 5 and 7, then the remaining two observations are: (1) 10, 11 (2) 3, 18 (3) 8, 13 (4) 1, 20
What This Question Tests
This question requires setting up and solving two simultaneous equations based on the given mean and variance of observations to find the values of the two unknown observations.
Concepts Tested
Formulas Used
Mean (x̄) = Σxᵢ / n
Variance (σ²) = (Σxᵢ² / n) - (x̄)²
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📋 Question Details
- Chapter
- Statistics
- Topic
- Mean and Variance
- Year
- 2021
- Shift
- 20 Jul Shift 1
- Q Number
- Q67
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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