Question:medium
In an experiment with 15 observations on \( x \), the results \( \sum x^2 = 2830 \) and \( \sum x = 170 \) were available. One observation (20) was wrong and was replaced by 30. The corrected variance is:
In an experiment with 15 observations on \( x \), the results \( \sum x^2 = 2830 \) and \( \sum x = 170 \) were available. One observation (20) was wrong and was replaced by 30. The corrected variance is:
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When correcting data, remember that errors in \( \sum x^2 \) are corrected by squaring the individual values, not by squaring the total sum error.
Updated On: May 1, 2026
- \( 9.3 \)
- \( 8.3 \)
- \( 188.6 \)
- \( 177.3 \)
- \( 78 \)
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The Correct Option is
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