document.write( "Question 823517: If there are 7 people in the room what are the chances they were born on the same day of the week? And explain why. \n" ); document.write( "

Algebra.Com's Answer #495641 by Edwin McCravy(20060) $\"\"$ $\"About$

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document.write( "If there are 7 people in the room, what\r\n" );
document.write( "are the chances they were born on the\r\n" );
document.write( "same day of the week? And explain why.\r\n" );
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document.write( "Suppose the seven people are Ann,\r\n" );
document.write( "Betty, Charles, Don, Edith, Fran, and\r\n" );
document.write( "George.\r\n" );
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document.write( "All 7 could have been born on the same\r\n" );
document.write( "day of the week in 7 ways.\r\n" );
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document.write( "So the numerator of the probability is\r\n" );
document.write( "7.\r\n" );
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document.write( "Ann could have been born on a day of\r\n" );
document.write( "the week in 7 ways.\r\n" );
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document.write( "For each of those 7 ways, Betty could\r\n" );
document.write( "have been born on a day of the week in\r\n" );
document.write( "7 ways.\r\n" );
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document.write( "For each of those 7 ways, Charles could\r\n" );
document.write( "have been born on a day of the week in\r\n" );
document.write( "7 ways.\r\n" );
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document.write( "For each of those 7 ways, Don could\r\n" );
document.write( "have been born on a day of the week in\r\n" );
document.write( "7 ways.\r\n" );
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document.write( "For each of those 7 ways, Edith could\r\n" );
document.write( "have been born on a day of the week in\r\n" );
document.write( "7 ways.\r\n" );
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document.write( "For each of those 7 ways, Fran could\r\n" );
document.write( "have been born on a day of the week in\r\n" );
document.write( "7 ways.\r\n" );
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document.write( "For each of those 7 ways, George could\r\n" );
document.write( "have been born on a day of the week in\r\n" );
document.write( "7 ways.\r\n" );
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document.write( "So the denominator of the desired\r\n" );
document.write( "probability is 7򊐟򊐟򊐟 or 7⁷.\r\n" );
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document.write( "So the probability is  =  =  \r\n" );
document.write( "or about 0.0000085.\r\n" );
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document.write( "Edwin

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