JEE Mains · Maths · STD 12 - 13. probability
Let the mean and the standard deviation of the probability distribution
| \(X\) | \(\alpha\) | \(1\) | \(0\) | \(-3\) |
| \(P(X)\) | \(\frac{1}{3}\) | \(K\) | \(\frac{1}{6}\) | \(\frac{1}{4}\) |
- A \(5\)
- B \(6\)
- C \(7\)
- D \(9\)
Answer & Solution
Correct Answer
(A) \(5\)
Step-by-step Solution
Detailed explanation
\( \frac{1}{3}+\mathrm{k}+\frac{1}{6}+\frac{1}{4}=1 \quad \Rightarrow \mathrm{k}=\frac{1}{4} \) \( \mu=\frac{\alpha}{3}+\frac{1}{4}-\frac{3}{4} \) \( \mu=\frac{\alpha}{3}-\frac{1}{2} \)…
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