document.write( "Question 601640: the total number of ways in which six 't' and four '-' signs can be arranged in a line such that no two '-' signs occur together is? \n" ); document.write( "

Algebra.Com's Answer #379936 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Think of it this way:\r\n" );
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document.write( "↏t↏t↏t↏t↏t↏t↏\r\n" );
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document.write( "We must pick 4 of the 7 boxes to put a single \"-\" in.\r\n" );
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document.write( "Answer: the number of combinations of 7 things taken 4 at a time \r\n" );
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document.write( "or 7C4 or C(7,4) =  = 35\r\n" );
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document.write( "Here are all 35 ways:\r\n" );
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document.write( " 1.  -t-t-t-ttt\r\n" );
document.write( " 2.  -t-t-tt-tt\r\n" );
document.write( " 3.  -t-t-ttt-t\r\n" );
document.write( " 4.  -t-t-tttt-\r\n" );
document.write( " 5.  -t-tt-t-tt\r\n" );
document.write( " 6.  -t-tt-tt-t\r\n" );
document.write( " 7.  -t-tt-ttt-\r\n" );
document.write( " 8.  -t-ttt-t-t\r\n" );
document.write( " 9.  -t-ttt-tt-\r\n" );
document.write( "10.  -t-tttt-t-\r\n" );
document.write( "11.  -tt-t-t-tt\r\n" );
document.write( "12.  -tt-t-tt-t\r\n" );
document.write( "13.  -tt-t-ttt-\r\n" );
document.write( "14.  -tt-tt-t-t\r\n" );
document.write( "15.  -tt-tt-tt-\r\n" );
document.write( "16.  -tt-ttt-t-\r\n" );
document.write( "17.  -ttt-t-t-t\r\n" );
document.write( "18.  -ttt-t-tt-\r\n" );
document.write( "19.  -ttt-tt-t-\r\n" );
document.write( "20.  -tttt-t-t-\r\n" );
document.write( "21.  t-t-t-t-tt\r\n" );
document.write( "22.  t-t-t-tt-t\r\n" );
document.write( "23.  t-t-t-ttt-\r\n" );
document.write( "24.  t-t-tt-t-t\r\n" );
document.write( "25.  t-t-tt-tt-\r\n" );
document.write( "26.  t-t-ttt-t-\r\n" );
document.write( "27.  t-tt-t-t-t\r\n" );
document.write( "28.  t-tt-t-tt-\r\n" );
document.write( "29.  t-tt-tt-t-\r\n" );
document.write( "30.  t-ttt-t-t-\r\n" );
document.write( "31.  tt-t-t-t-t\r\n" );
document.write( "32.  tt-t-t-tt-\r\n" );
document.write( "33.  tt-t-tt-t-\r\n" );
document.write( "34.  tt-tt-t-t-\r\n" );
document.write( "35.  ttt-t-t-t-\r\n" );
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document.write( "Edwin

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