Q74.The mean and variance for seven observations are 8 and 16 respectively. If 5 of the observations are 2, 4, 10, 12, 14, then the product of the remaining two observations is (1) 48 (2) 45 (3) 49 (4) 40
What This Question Tests
This question requires applying the formulas for mean and variance to a set of observations, including finding missing data points, and then calculating their product.
Concepts Tested
Formulas Used
Mean (x̄) = Σxᵢ / n
Variance (σ²) = (Σxᵢ² / n) - (x̄)²
📚 NCERT Sections This Tests
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📋 Question Details
- Chapter
- Statistics
- Topic
- Mean and variance of grouped data
- Year
- 2019
- Shift
- 08 Apr Shift 1
- Q Number
- Q74
- Type
- MCQ
- NCERT Ref
- Class 11 Maths Ch 15: Statistics
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