Question:medium
Let $x_1, x_2, \ldots, x_n$ be $n$ observations such that $\sum x_i^2 = 400$ and $\sum x_i = 80$. Then a possible value of $n$ is
Let $x_1, x_2, \ldots, x_n$ be $n$ observations such that $\sum x_i^2 = 400$ and $\sum x_i = 80$. Then a possible value of $n$ is
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Use Cauchy–Schwarz inequality for such sum-of-squares problems.
Updated On: Apr 30, 2026
- $15$
- $10$
- $9$
- $12$
- $18$
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The Correct Option is B
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