मराठी

Let A and B be independent events with P(A) = 0.3 and P(B) = 0.4. Find (i) P(A ∩ B) (ii) P(A ∪ B) (iii) P (A|B) (iv) P (B|A)

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प्रश्न

Let A and B be independent events with P (A) = 0.3 and P (B) = 0.4. Find 

  1. P (A ∩ B)
  2. P (A ∪ B)
  3. P (A | B)
  4. P (B | A)
बेरीज
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उत्तर

It is given that P (A) = 0.3 and P (B) = 0.4

If A and B are independent events, then

(i) P(A ∩ B) = P(A) · P(B)

P(A ∩ B) = 0.3 × 0.4

P(A ∩ B) = 0.12

(ii) P(A ∪ B) = P(A) + P(B) - P(A ∩ B)

P(A ∪ B) = 0.3 + 0.4 - 0.12

P(A ∪ B) = 0.58

(iii) P(A | B) = `(P(A ∩ B))/(P(B))`

P(A | B) = `0.12/0.4`

P(A | B) `= 3/10`

P(A | B) `= 0.3`

(iv) P(B | A) = `(P(A ∩ B))/(P(A))`

P(B | A) = `0.12/0.3`

P(B | A) = 0.4

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पाठ 13: Probability - Exercise 13.2 [पृष्ठ ५४७]

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एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
पाठ 13 Probability
Exercise 13.2 | Q 8. | पृष्ठ ५४७

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