document.write( "Question 980630: A committee of seven members is to be formed from a group of 11 members. The probability that a certain married couple will either serve together or not at all is. \n" ); document.write( "

Algebra.Com's Answer #601754 by Edwin McCravy(20055) $\"\"$ $\"About$

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A committee of seven members is to be formed from a group of 11 members. The probability that a certain married couple will either serve together or neither serves.
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document.write( "The numerator is the number of ways they serve together or neither serves.\r\n" );
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document.write( "Case 1. They serve together.\r\n" );
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document.write( "Then we choose the remaining 5 to serve from the remaining 9 in 9C5 ways.\r\n" );
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document.write( "Case 2. Neither serves. Then we choose the 7 to serve from the remaining 9\r\n" );
document.write( "in 9C7 ways.\r\n" );
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document.write( "Total successful ways: 9C5 + 9C7 = 126+36 = 162\r\n" );
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document.write( "Total ways to choose any 7:  11C7 = 330\r\n" );
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document.write( "Probability = 162/330 = 27/55\r\n" );
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document.write( "Edwin

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