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A man A speaks truth in 70% of the cases...

A man A speaks truth in 70% of the cases while another man B speaks truth in 60% of the cases. Find the probability of an event in which they agree with one another.

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To solve the problem, we need to find the probability that two men, A and B, agree with each other based on their probabilities of speaking the truth. Let's break this down step by step. ### Step 1: Define the Events Let: - \( E_1 \): Event that A speaks the truth. - \( E_2 \): Event that B speaks the truth. ### Step 2: Assign Probabilities From the problem statement: - Probability that A speaks the truth: \[ P(E_1) = 0.7 = \frac{7}{10} \] - Probability that B speaks the truth: \[ P(E_2) = 0.6 = \frac{6}{10} \] ### Step 3: Calculate the Probabilities of Speaking False - Probability that A speaks false (does not speak the truth): \[ P(E_1') = 1 - P(E_1) = 1 - \frac{7}{10} = \frac{3}{10} \] - Probability that B speaks false: \[ P(E_2') = 1 - P(E_2) = 1 - \frac{6}{10} = \frac{4}{10} \] ### Step 4: Identify the Cases for Agreement A and B can agree in two scenarios: 1. Both A and B speak the truth. 2. Both A and B speak false. ### Step 5: Calculate the Probability of Each Case 1. **Both speak the truth**: \[ P(E_1 \cap E_2) = P(E_1) \times P(E_2) = \frac{7}{10} \times \frac{6}{10} = \frac{42}{100} \] 2. **Both speak false**: \[ P(E_1' \cap E_2') = P(E_1') \times P(E_2') = \frac{3}{10} \times \frac{4}{10} = \frac{12}{100} \] ### Step 6: Combine the Probabilities Since these two cases are mutually exclusive, we can add the probabilities: \[ P(\text{A and B agree}) = P(E_1 \cap E_2) + P(E_1' \cap E_2') = \frac{42}{100} + \frac{12}{100} = \frac{54}{100} \] ### Step 7: Final Probability Thus, the probability that A and B agree with one another is: \[ P(\text{A and B agree}) = 0.54 \] ### Final Answer The final probability that A and B agree with one another is \( \frac{54}{100} \) or 0.54. ---

To solve the problem, we need to find the probability that two men, A and B, agree with each other based on their probabilities of speaking the truth. Let's break this down step by step. ### Step 1: Define the Events Let: - \( E_1 \): Event that A speaks the truth. - \( E_2 \): Event that B speaks the truth. ### Step 2: Assign Probabilities ...
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NAGEEN PRAKASHAN ENGLISH-PROBABIILITY-Miscellaneous Exercise
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