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The probability that a car being filled with petrol will also need an oil change is 0.30; the probability that it needs a new oil filter is 0.40; and the probability that both the oil - Mathematics

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प्रश्न

The probability that a car being filled with petrol will also need an oil change is 0.30; the probability that it needs a new oil filter is 0.40; and the probability that both the oil and filter need changing is 0.15. If the oil had to be changed, what is the probability that a new oil filter is needed?

योग
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उत्तर

Let A be the event of changing oil, B be the event of changing oil filter.

Given P(A) = 0.30

P(B) = 0.40

P(A ∩ B) = 0.15

Probability of new oil filter B needed when the oil A changed is

P(B/A) = `("P"("B" ∪ "A"))/("P"("A"))`

= `0.15/0.30`

= `15/30`

= `1/2`

= 0.5

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 12: Introduction to probability theory - Exercise 12.3 [पृष्ठ २५९]

APPEARS IN

सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 11 TN Board
अध्याय 12 Introduction to probability theory
Exercise 12.3 | Q 7. (i) | पृष्ठ २५९

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