document.write( "Question 1142523: A researcher wanting to investigate the prevalence of smoking among teens selected a random sample of 200 teens and asked whether or not they smoked. This information is recorded in the following table:\r
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\n" ); document.write( " Male 38 82
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\n" ); document.write( "\n" ); document.write( "a) What is the probability of randomly selecting a teen that is female?
\n" ); document.write( "b) What is the probability of randomly selecting a teen that is female and smokes?
\n" ); document.write( "c) What is the probability of randomly selecting a teen that smokes given that he is
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Algebra.Com's Answer #763209 by ikleyn(52805) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "First, I checked that the sum of all numbers in the Table is 200 : 38 + 82 + 24 + 56 = 200. ! Correct !\r
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document.write( "(a)  P =  =  =  =  = 0.4 = 40%.\r\n" );
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document.write( "(b)  P =  =  =  = 0.59 = 59%.\r\n" );
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document.write( "         To the total number of female teens add the number of smoking male teens;  then relate the sum to 200.\r\n" );
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document.write( "         Very simple and does not require additional explanations.\r\n" );
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document.write( "(c)  P =  =  =  = 0.475 = 47.5%.\r\n" );
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document.write( "     It looks OBVIOUS to me, since in this case you, actually, select among 80 male teens.\r\n" );
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