document.write( "Question 1119077: Of 10 girls in a class, three have blue eyes. Two of the girls are chosen at random. Find the probability that exactly one has blue eyes. \n" ); document.write( "

Algebra.Com's Answer #734525 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "To solve this problem, you need to answer 2 questions:\r\n" );
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document.write( "1.  How many pairs of girls can be formed of 10 girls ?\r\n" );
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document.write( "    The answer is   =  = 45 pairs.\r\n" );
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document.write( "2.  How many pairs are there where exactly one girl has blue eyes ?\r\n" );
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document.write( "    You may choose first blue-eyed girl and add any other of 7 remaining non-blue-eyed girls: 7 options in all.\r\n" );
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document.write( "    You can do the same with the other and the third blue-eyed girl.\r\n" );
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document.write( "    In this way you will get  7 + 7 + 7 = 21 pairs of girls, where only one girl is blue eyed.\r\n" );
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document.write( "3.  Now you can easily answer the problem question:\r\n" );
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document.write( "        the probability under the question is   = .\r\n" );
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