Q85.Let n be an odd natural number such that the variance of 1, 2, 3, 4, … , n is 14. Then n is equal to ________.
What This Question Tests
This problem directly tests the knowledge of the formula for the variance of the first 'n' natural numbers and solving for 'n' given the variance.
Concepts Tested
Formulas Used
Variance (σ²) = (Σxᵢ²/n) - (Σxᵢ/n)²
Σn = n(n+1)/2
Σn² = n(n+1)(2n+1)/6
📚 NCERT Sections This Tests
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.
1.18 — A Point Charge Of 2.0 Mc Is At The Centre Of A Cubic Gaussian
Physics Class 11 · Chapter 1
1.18 A point charge of 2.0 mC is at the centre of a cubic Gaussian surface 9.0 cm on edge. What is the net electric flux through the surface?
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
📋 Question Details
- Chapter
- Statistics
- Topic
- Variance of Natural Numbers
- Year
- 2021
- Shift
- 27 Aug Shift 1
- Q Number
- Q85
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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