document.write( "Question 734926: In reviewing my stats and probability I've been doing practice SAT questions. This is one I've encountered that seems inaccurate but I am not certain. Here goes:\r
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document.write( "There is a class of 20 girls. 15 have brown hair and 12 have brown eyes. If a random girl with brown hair is selected, what is the chance she also has brown eyes?\r
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document.write( "Now, I have approached this as follows:\r
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document.write( "P(BH) = 3/4
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document.write( "P(BE) = 3/5
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document.write( "P(BH and BE) = 9/20\r
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document.write( "Thus of the 15 girls with brown hair 9/20ths of them have brown eyes too. Or:\r
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document.write( "15 * 9/20 = 27/4 = 6.75 -> aprox. 7/15 chance a girl with brown hair will have brown eyes also.\r
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document.write( "The app I'm using gives an explanation that says only 7 girls have brown hair and brown eyes and this can be easily shown with a venn diagram. But in constructing a venn diagram I feel that there is not enough info presented to determine this easily. What am I missing? Or is the question flawed?\r
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document.write( "Thanks in advance!! \n" );
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Algebra.Com's Answer #449191 by lynnlo(4176)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( " |