Q70.Let ๐ be the mean and ๐ be the standard deviation of the distribution ๐๐ 0 1 2 3 4 5 ๐๐ ๐+ 2 2๐ ๐2 - 1 ๐2 - 1 ๐2 + 1 ๐- 3 where ๐ด๐๐= 62. If ๐ฅ denotes the greatest integer โค๐ฅ, then๐2 + ๐2 is equal to (1) 9 (2) 8 (3) 7 (4) 6
What This Question Tests
This question tests the ability to calculate the mean and standard deviation for a discrete frequency distribution, involving an unknown constant 'k' which needs to be determined first.
Concepts Tested
Formulas Used
Mean (ฮผ) = ฮฃ(Xi * fi) / ฮฃfi
Variance (ฯ^2) = (ฮฃ(Xi^2 * fi) / ฮฃfi) - ฮผ^2
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๐ Question Details
- Chapter
- Statistics
- Topic
- Mean and standard deviation of a discrete distribution
- Year
- 2023
- Shift
- 10 Apr Shift 2
- Q Number
- Q70
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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