document.write( "Question 602109: At a certain college, 55% of the students are female, and 21% of the students major in civil engineering. Furthermore, 8% of the students both are female and major in civil engineering. \r
\n" ); document.write( "\n" ); document.write( "(a) What is the probability that a randomly selected female student majors in civil engineering? Round your answer to 2 decimal places.
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Algebra.Com's Answer #380134 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
55% of the students are female,
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document.write( "P(F) = .55\r\n" );
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\n" ); document.write( "21% of the students major in civil engineering.
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document.write( "P(C) = .21\r\n" );
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\n" ); document.write( "8% of the students both are female and major in civil engineering.
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document.write( "P(F&C) = .08\r\n" );
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\n" ); document.write( "(a) What is the probability that a randomly selected female student majors in civil engineering?
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document.write( "Re-word that thinking about what's GIVEN: \"What is the probability that a student majors in CE GIVEN that the student is a female\".\r\n" );
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document.write( "P(C|F) = ?\r\n" );
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document.write( "Use the formula:\r\n" );
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document.write( "P(C|F) = P(C&F)/P(F) \r\n" );
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document.write( "We have P(F) = .55 \r\n" );
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document.write( "We have P(C&F) because P(F&C) = .08 is the same thing \r\n" );
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document.write( "P(F&C) = .08\r\n" );
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document.write( "P(C|F) = P(C&F)/P(F) = .08/.55 = .1454545455\r\n" );
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document.write( "Rounded to 2 decimal places:   .15\r\n" );
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\n" ); document.write( "(b) What is the probability that a randomly selected civil engineering major is female? Round your answer to 2 decimal places
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document.write( "Re-word that thinking about what's GIVEN: \"What is the probability that a student is a female GIVEN THAT she majors in CE\".\r\n" );
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document.write( "P(F|C) = ?\r\n" );
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document.write( "Use the formula swapping F and C from the previous example:\r\n" );
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document.write( "P(F|C) = P(F&C)/P(C) \r\n" );
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document.write( "We have P(C) = .21 \r\n" );
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document.write( "We have P(F&C) = .08 \r\n" );
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document.write( "P(F|C) = P(F&C)/P(C) = .08/.21 = .380952381\r\n" );
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document.write( "Rounded to 2 decimal places:   .38\r\n" );
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document.write( "Edwin
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