JEE Mains · Maths · STD 12 - 13. probability
The probability distribution of a random variable X is given below:
| X | \(4k\) | \(\frac{30}{7} k\) | \(\frac{32}{7} k\) | \(\frac{34}{7} k\) | \(\frac{36}{7} k\) | \(\frac{38}{7} k\) | \(\frac{40}{7} k\) | \(6k\) |
| P(X) | \(\frac{2}{15}\) | \(\frac{1}{15}\) | \(\frac{2}{15}\) | \(\frac{1}{5}\) | \(\frac{1}{15}\) | \(\frac{2}{15}\) | \(\frac{1}{5}\) | \(\frac{1}{15}\) |
- A \(\frac{3}{5}\)
- B \(\frac{8}{15}\)
- C \(\frac{11}{15}\)
- D \(\frac{14}{15}\)
Answer & Solution
Correct Answer
(C) \(\frac{11}{15}\)
Step-by-step Solution
Detailed explanation
\(E(X)=\sum X_{i}P(X_{i})=\frac{526k}{15\times7}=\frac{263}{15}\Rightarrow k=\frac{7}{2}\)X 14 15 16 17 18 19 20 21 \(P ( X )\) \(\frac{2}{15}\) \(\frac{1}{15}\) \(\frac{2}{15}\) \(\frac{1}{5}\) \(\frac{1}{15}\) \(\frac{2}{15}\) \(\frac{1}{5}\) \(\frac{1}{15}\)…
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