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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 following table summarizes their resp - Mathematics and Statistics

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Question

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 following 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 the person had Throat surgery given that the person was unsatisfied.

Sum

Solution

Let event F: The patient had a throat surgery,

event G: The patient was unsatisfied.

Given, n(S) = 200

n(F ∩ G) = 25

∴ P(F ∩ G) = `(n(F ∩ G))/(n(S))`

= `25/200`

n(G) = 40

∴ P(G) = `(n(G))/(n(S))`

∴ P(G) = `40/200`

∴ Required probability = P(F/G)

= `(P(F ∩ G))/(P(G))`

= `(25/200)/(40/200)`

= `25/200 xx200/40`

= `25/40`

= `5/8`

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Chapter 9: Probability - Exercise 9.3 [Page 206]

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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

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