Q72.If the variance of the terms in an increasing A. P. b1b2, b3, … … . . , b11 is 90 then the common difference of this A. P. is
What This Question Tests
This question requires recalling or deriving the formula for the variance of terms in an arithmetic progression and applying it to find the common difference given the variance and number of terms.
Concepts Tested
Formulas Used
Variance σ² = (d²(N²-1))/12
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📋 Question Details
- Chapter
- Statistics
- Topic
- Variance of an arithmetic progression
- Year
- 2020
- Shift
- 02 Sep Shift 2
- Q Number
- Q72
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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