Consider 5 independent Bernoulli’s trials each with probability of success p. If the probability of atleast one failure is greater than or equal to \(31\over 32\), then p lies in the interval
Solution : Here, n = 5 and r \(\ge\) 1 \(\therefore\) p(X = r) = \(^nC_r\) \(p^{n-r}\) \(q^r\) P(X \(\ge\) 1) = 1 – P(X = 0) = 1 – \(^5C_0 . p^5 . q^0\) \(\ge\) \(31\over 32\) [Given] \(\implies\) \(p^5\) \(\le\) 1 – \(31\over 32\) = \(1\over 32\) \(\therefore\) p \(\le\) \(1\over 2\) and […]