Question:medium
For two data sets, each of size 5, the variances are given to be 4 and 5 and the corresponding means are given to be 2 and 4, respectively. The variance of the combined data set is
For two data sets, each of size 5, the variances are given to be 4 and 5 and the corresponding means are given to be 2 and 4, respectively. The variance of the combined data set is
Show Hint
For combined variance problems:
First find combined mean, then use the combined variance formula.
Never directly average variances.
Updated On: Apr 30, 2026
- \( \frac{15}{2} \)
- \(6\)
- \( \frac{13}{2} \)
- \( \frac{5}{2} \)
- \( \frac{11}{2} \)
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The Correct Option is C
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