Q74.If the mean of the data: 7, 8, 9, 7, 8, 7, λ, 8 is 8 , then the variance of this data is (1) 9 (2) 2 8 (3) 7 (4) 1 8
What This Question Tests
This question first requires calculating a missing data value using the given mean and then computing the variance of the complete dataset.
Concepts Tested
Formulas Used
Mean = (Σx_i) / N
Variance = (Σx_i²) / N - (Mean)²
📚 NCERT Sections This Tests
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8.17 Complete each synthesis by giving missing starting material, reagent or products
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13.2 Obtain the binding energy of the nuclei 5626Fe and 20983 Bi in units of MeV from the following data: m ( 5626Fe ) = 55.934939 u m ( 20983 Bi ) = 208.980388 u
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1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
📋 Question Details
- Chapter
- Statistics
- Topic
- Mean and Variance
- Year
- 2018
- Shift
- 15 Apr Shift 2 Online
- Q Number
- Q74
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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