JEE Mains · Maths · STD 12 - 13. probability
If the mean of the following probability distribution of a random variable \(X\);
| \(X\) | \(0\) | \(2\) | \(4\) | \(6\) | \(8\) |
| \(P(X)\) | \(a\) | \(2a\) | \(a+b\) | \(2b\) | \(3b\) |
- A \(\frac{581}{81}\)
- B \(\frac{566}{81}\)
- C \(\frac{173}{27}\)
- D \(\frac{151}{27}\)
Answer & Solution
Correct Answer
(B) \(\frac{566}{81}\)
Step-by-step Solution
Detailed explanation
\( \sum P_i=1 \) \( a+2 a+a+b+2 b+3 b=1 \) \( 4 a+6 b=1 \).................(\(i\)) \( E(x)=\text { mean }=\frac{46}{9}\)…
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