JEE Mains · Maths · STD 12 - 13. probability
If the mean and the variance of a binomial variate \(X\) are \(2\) and \(1\) respectively, then the probability that \(X\) takes a value greater than or equal to one is
- A \(\frac{9}{16}\)
- B \(\frac{3}{4}\)
- C \(\frac{1}{16}\)
- D \(\frac{15}{16}\)
Answer & Solution
Correct Answer
(D) \(\frac{15}{16}\)
Step-by-step Solution
Detailed explanation
Letmean \(=\mathrm{np}=2\) and ......\((1)\) variance \(=\mathrm{npq}=1\) ......\((2)\) On solvingeqn \((1)\) and \(( 2)\), we get \(q=\frac{1}{2}\) and \(p=\frac{1}{2}\) Fromeqn \((1)\), we have \(n=4\)…
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