Q75.Mean of 5 observations is 7 . If four of these observations are 6, 7, 8, 10 and one is missing then the variance of all the five observations is : (1) 4 (2) 6 (3) 8 (4) 2
What This Question Tests
The question tests the calculation of a missing observation given the mean, and then computing the variance for all observations using the standard formula.
Concepts Tested
Formulas Used
Mean (x̄) = (Σxᵢ)/N
Variance (σ²) = (Σxᵢ²)/N - (x̄)²
📚 NCERT Sections This Tests
1.3 — Define The Following Terms:
Chemistry Class 11 · Chapter 1
1.3 Define the following terms: (i) Mole fraction (ii) Molality (iii) Molarity (iv) Mass percentage.
8.17 — Complete Each Synthesis By Giving Missing Starting Material, Reagent Or Products
Chemistry Class 12 · Chapter 8
8.17 Complete each synthesis by giving missing starting material, reagent or products
4.13 — How Is The Variability In Oxidation States Of Transition Metals Different From
Chemistry Class 11 · Chapter 4
4.13 How is the variability in oxidation states of transition metals different from that of the non transition metals? Illustrate with examples.
📋 Question Details
- Chapter
- Statistics
- Topic
- Mean and Variance
- Year
- 2013
- Shift
- 22 Apr Online
- Q Number
- Q75
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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