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Given that the events A and B are such t...

Given that the events A and B are such that `P(A)=1/2, P(AuuB)=3/5a n d\ P(B)=pdot` Find `p` if they are i. mutually exclusive, ii. independent.

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To solve the problem, we need to find the value of \( p \) given the probabilities of events A and B under two different conditions: mutually exclusive and independent. ### Given: - \( P(A) = \frac{1}{2} \) - \( P(A \cup B) = \frac{3}{5} \) - \( P(B) = p \) ### Part 1: When A and B are Mutually Exclusive 1. **Understanding Mutually Exclusive Events**: - If A and B are mutually exclusive, then \( P(A \cap B) = 0 \). - The formula for the union of two events is: \[ P(A \cup B) = P(A) + P(B) - P(A \cap B) \] - Substituting \( P(A \cap B) = 0 \): \[ P(A \cup B) = P(A) + P(B) \] 2. **Substituting the Given Values**: - We know \( P(A \cup B) = \frac{3}{5} \), \( P(A) = \frac{1}{2} \), and \( P(B) = p \): \[ \frac{3}{5} = \frac{1}{2} + p \] 3. **Solving for p**: - Rearranging the equation: \[ p = \frac{3}{5} - \frac{1}{2} \] - Finding a common denominator (which is 10): \[ p = \frac{6}{10} - \frac{5}{10} = \frac{1}{10} \] ### Part 2: When A and B are Independent 1. **Understanding Independent Events**: - If A and B are independent, then: \[ P(A \cap B) = P(A) \cdot P(B) \] 2. **Using the Union Formula**: - We can still use the union formula: \[ P(A \cup B) = P(A) + P(B) - P(A \cap B) \] - Substituting for \( P(A \cap B) \): \[ P(A \cup B) = P(A) + P(B) - P(A) \cdot P(B) \] 3. **Substituting the Given Values**: - Plugging in the known values: \[ \frac{3}{5} = \frac{1}{2} + p - \left(\frac{1}{2} \cdot p\right) \] 4. **Rearranging the Equation**: - Simplifying the equation: \[ \frac{3}{5} = \frac{1}{2} + p - \frac{p}{2} \] - Combine like terms: \[ \frac{3}{5} = \frac{1}{2} + \frac{2p}{2} - \frac{p}{2} = \frac{1}{2} + \frac{p}{2} \] 5. **Finding a Common Denominator**: - The common denominator is 10: \[ \frac{3}{5} = \frac{6}{10} \quad \text{and} \quad \frac{1}{2} = \frac{5}{10} \] - Thus: \[ \frac{6}{10} = \frac{5}{10} + \frac{p}{2} \] 6. **Solving for p**: - Rearranging gives: \[ \frac{p}{2} = \frac{6}{10} - \frac{5}{10} = \frac{1}{10} \] - Therefore: \[ p = \frac{1}{10} \cdot 2 = \frac{1}{5} \] ### Final Answers: - For mutually exclusive events, \( p = \frac{1}{10} \). - For independent events, \( p = \frac{1}{5} \).

To solve the problem, we need to find the value of \( p \) given the probabilities of events A and B under two different conditions: mutually exclusive and independent. ### Given: - \( P(A) = \frac{1}{2} \) - \( P(A \cup B) = \frac{3}{5} \) - \( P(B) = p \) ### Part 1: When A and B are Mutually Exclusive ...
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NAGEEN PRAKASHAN ENGLISH-PROBABIILITY-Exercise 13.2
  1. If P(A) =3/5and P(B) =1/5, find P(AnnB)if A and B are independent even...

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  2. Two cards are drawn at random and without replacement from a pack of ...

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  3. A box of oranges is inspected by examining three randomly selected o...

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  4. A fair coin and an in biased die are tossed. Let A be the event head ...

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  5. A die marked 1, 2, 3 in red and 4, 5, 6 in green is tossed. Let A be ...

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  6. Let E and F be events with P (E) =3/5, P (F) =3/(10)and P(EnnF)=1/5. A...

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  7. Given that the events A and B are such that P(A)=1/2, P(AuuB)=3/5a n d...

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  8. Let A and B be independent events with P(A) = 0. 3and P(B) = 0. 4Find...

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  9. If A and B are two events such that P(A) = (1)/(4), P(B) = (1)/(2) and...

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  10. Events A and B are such that P(A)=1//2,P(B)=7//12, and P (not A or not...

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  11. Given two independent events A and B such thatP(A) = 0. 3,P(B) = 0. 6...

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  12. A die is tossed thrice. Find the probability of getting an odd number ...

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  13. Two balls are drawn at random with replacement from a box containing 1...

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  14. Probability of solving specific problem independently by A and B are 1...

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  15. One card is drawn at random from a well shuffled deck of 52 cards. I...

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  16. In a hostel 60% of the students read Hindi news paper, 40% read Englis...

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  17. The probability of obtaining an even prime number on each die, when a ...

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  18. Two events A and B will be independent, if(A) A and B are mutually ex...

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