document.write( "Question 1154579: Assume that each child who is born is equally likely to be a boy or a girl. If a family has two children, what is the probability that both are girls given that (a) the eldest is a girl, (b) atleast one is a girl? \n" ); document.write( "

Algebra.Com's Answer #777035 by ikleyn(52784) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( " The simplest way to solve this problem is, probably, to use the sample space conception.\r
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document.write( "(a)  In this case, the sample space consists of two pairs, ordered by the age \r\n" );
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document.write( "         (youngest,eldest) = (boy,girl)  and  (youngest,eldest) = (girl,girl).\r\n" );
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document.write( "     Both these pairs (both elements of the sample space) are equally likelihood.\r\n" );
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document.write( "     The favorable pair is only one (youngest,eldest) = (girl,girl).\r\n" );
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document.write( "     Therefore, the probability in case (a)  P =  = .\r\n" );
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document.write( "(b)  In this case, the sample space consists of two pairs \r\n" );
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document.write( "         (boy,girl)  and  (girl,girl)    (the order in pairs does not matter).\r\n" );
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document.write( "     Both these pairs (both elements of the sample space) are equally likelihood.\r\n" );
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document.write( "     The favorable pair is only one (girl,girl).\r\n" );
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document.write( "     Therefore, the probability in case (b)  P =  = .\r\n" );
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