Q72.If the mean and standard deviation of 5 observations x1, x2, x3, x4, x5 are 10 and 3, respectively, then the variance of 6 observations x1, x2, … , x5 and −50 is equal to (1) 582.5 (2) 507.5 (3) 509.5 (4) 586.5
What This Question Tests
This question requires calculating the variance of a new set of observations after adding a data point, using the given mean and standard deviation of the original set.
Concepts Tested
Formulas Used
Variance = (sum(xi^2)/N) - (mean)^2
New mean and variance calculations
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📋 Question Details
- Chapter
- Statistics
- Topic
- Mean and variance
- Year
- 2019
- Shift
- 10 Jan Shift 2
- Q Number
- Q72
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 15: Statistics
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