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महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता ११ वी

Two hundred patients who had either Eye surgery or Throat surgery were asked whether they were satisfied or unsatisfied regarding the result of their surgery The follwoing table summarizes their resp

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प्रश्न

Two hundred patients who had either Eye surgery or Throat surgery were asked whether they were satisfied or unsatisfied regarding the result of their surgery

The follwoing table summarizes their response:

Surgery Satisfied Unsatisfied Total
Throat 70 25 95
Eye 90 15 105
Total 160 40 200

If one person from the 200 patients is selected at random, determine the probability that the person was satisfied given that the person had Throat surgery.

बेरीज
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उत्तर

Let T ≡ set of people having throat surgery

E ≡ set of people having eye surgery

N ≡ set of people who were unsatisfied

Then n(T) = 95, n(E) = 105, n(N) = 40

One person is chosen from 200 persons in 200C1 = 200 ways.

∴ n(S) = 200.

It is given that person had throat surgery

∴ sample space is T for which n(T) = 95

Out of these favourable cases are 70 i.e., those who are satisfied

∴ the required probability = `70/95 = 14/19`.

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पाठ 9: Probability - Exercise 9.3 [पृष्ठ २०६]

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