Q68.If the mean and variance of five observations are 24 and 194 respectively and the mean of first four 5 25 observations is 7 , then the variance of the first four observations in equal to 2 (1) 4 (2) 77 5 12 (3) 5 (4) 105 4 4
What This Question Tests
The question tests the understanding and application of the definitions of mean and variance, requiring calculation of sums of observations and sums of squares for different sets of data.
Concepts Tested
Formulas Used
Mean = (Σx_i) / n
Variance = (Σx_i^2) / n - (Mean)^2
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📋 Question Details
- Chapter
- Statistics
- Topic
- Mean and Variance
- Year
- 2024
- Shift
- 29 Jan Shift 2
- Q Number
- Q68
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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