quiz3-key

# quiz3-key - Let B denote the event that the chosen sample...

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Quiz 3. September 15, 2010 Seat # _________ Name: _________________________ Closed book and notes. No calculators. Remember. For T/F questions, a statement is true only if it is always true. Below, assume that all probabilities mentioned are not zero. 1. (2 pts) The definition of conditional probability is P( A | B ) = P( B ) P( A B ) hhhhhhhhh 2. (2 pts) T F P( A ) = P( A | B ) P( B ) + P( A | B ) P( B ). 3. (2 pts) T F P( A | B )P( B ) = P( B | A )P( A ). 4. (2 pts) T F P( A | B ) = 1 P( A | B ). For Question 5, consider Montgomery and Runger’s Problem 2–63. Samples of emissions from three suppliers are classified for conformance to air-quality standards. The results from 100 samples are summarized in the table. conforms iiiiiiiiiiiiiii yes no 1 22 8 supplier 2 25 5 3 30 10 Consider the experiment of choosing one of the 100 samples, each with equal likelihood. Let A denote the event that the chosen sample conforms to specifications.
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Unformatted text preview: Let B denote the event that the chosen sample is from supplier 2. 5. (2 pts) Determine the value of P( A ′ | B ). (Show your logic.) P( A ′ | B ) = fraction of B in A ′ = 25 + 5 5 hhhhhh = 6 1 hh ← or P( A ′ | B ) = P( B ) P( A ′ ∩ B ) hhhhhhhhhh = (25 + 5) / 100 5 / 100 hhhhhhhhhhhh = 6 1 hh ← or P( A ′ | B ) = P( B ) P( B | A ′ ) P( A ′ ) hhhhhhhhhhhh = (25 + 5) / 100 [5 / (8 + 5 + 1 )][(8 + 5 + 10) / 100] hhhhhhhhhhhhhhhhhhhhhhhhhhhh = 6 1 hh ← ______________________________________________________________________ Write on the back any concerns about the weekly quizzes or the course in general. IE 230 – Page 1 of 1 – Schmeiser...
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## This note was uploaded on 04/25/2011 for the course IE 230 taught by Professor Xangi during the Fall '08 term at Purdue University.

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