

InterviewSolution
Saved Bookmarks
1. |
Four candidates A, B, C, D have applied for the assignment to each a school cricket team.If A is twice as likely to be selected as B and B and C are given about the same chance of being selected, while C is twice as likely to be selected as D, what are the probabilities that – (i) C will be selected? (ii) A will not be selected. |
Answer» Let E1, E2, E3, E4 denote the events that the person A, B C and D is selected respectively. Also, let the probability of selecting D be ‘k’. Then, P(E4) = k ∴ P(E1) = 2P(E2), P(E2) P(E3) = 2P(E4) = 2k = 2 × 2k = 4k Since E1, E2, E3, E4 are mutually exclusive and exhaustive events so– P(E1 ∪ E2 ∪ E3 ∪ E4) = P(E1) + P(E2) + P(E3) + P(E4) ⇒ 1 = 4k + 2k + 2k + k ⇒ 9k = 1 ⇒ k = 1/9 (i) P(E3) = 2k = \(\frac{2}{9}\) (ii) P(E1’) = 1 – p(E1) = 1 – 4k = 1 – 4(10) = 1 − \((\frac{1}{9})\) = 1 - \(\frac{4}{9}\) = \(\frac{5}{9}\) |
|