Question:medium
Let the six numbers \( a_1, a_2, a_3, a_4, a_5, a_6 \) be in A.P., and \( a_1 + a_3 = 10 \). If the mean of these six numbers is \( \frac{19}{2} \) and their variance is \( \sigma^2 \), then \( 8\sigma^2 \) is equal to:
Let the six numbers \( a_1, a_2, a_3, a_4, a_5, a_6 \) be in A.P., and \( a_1 + a_3 = 10 \). If the mean of these six numbers is \( \frac{19}{2} \) and their variance is \( \sigma^2 \), then \( 8\sigma^2 \) is equal to:
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Convert given conditions into equations in \(a_1\) and \(d\), find actual terms, then apply variance formula carefully.
Updated On: May 8, 2026
- \(220 \)
- \(210 \)
- \(200 \)
- \(105 \)
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The Correct Option is B
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