JEE Mains · Maths · STD 11 - 13. statistics
Let \(\mu\) be the mean and \(\sigma\) be the standard deviation of the distribution
| \(X_i\) | \(0\) | \(1\) | \(2\) | \(3\) | \(4\) | \(5\) |
| \(f_i\) | \(k+2\) | \(2k\) | \(K^{2}-1\) | \(K^{2}-1\) | \(K^{2}-1\) | \(k-3\) |
- A \(8\)
- B \(7\)
- C \(6\)
- D \(9\)
Answer & Solution
Correct Answer
(A) \(8\)
Step-by-step Solution
Detailed explanation
\(\sum f _{ i }=62\) \(3 k ^2+16 k -12 k -64=0\) \(k =\text { or }-\frac{16}{3}(\text { rejected) }\) \(\mu=\frac{\sum f _{ i } x _{ i }}{\sum f _{ i }}\) \(\mu=\frac{8+2(15)+3(15)+4(17)+5}{62}=\frac{156}{62}\)…
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