document.write( "Question 370342: a. Suppose we have a group of 8 students sitting on a long bench.
\n" ); document.write( "Four of the eight insist on sitting side-by-side. In how many ways can the eight students be seated on the bench?\r
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\n" ); document.write( "\n" ); document.write( "b. Two of the eight insisting on not sitting side by side. In how many ways can the eight students be seated on the bench?\r
\n" ); document.write( "\n" ); document.write( "thanks alot
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Algebra.Com's Answer #264009 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
a. Suppose we have a group of 8 students sitting on a long bench.
\n" ); document.write( "Four of the eight insist on sitting side-by-side. In how many ways can the eight students be seated on the bench?
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\n" ); document.write( "Treat the four as a block that can be arranged 4! ways
\n" ); document.write( "Treat the other four plus the block as 5 persons that
\n" ); document.write( "can be arranged in 5! ways
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\n" ); document.write( "Total arrangements = 4!*5! = 2880 arrangements
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\n" ); document.write( "\n" ); document.write( "b. Two of the eight insisting on not sitting side by side. In how many ways can the eight students be seated on the bench?
\n" ); document.write( "# of unrestricted arrangements = 8!
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\n" ); document.write( "# of arrangements with the two sitting side-by-side = 14
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\n" ); document.write( "Ans: 8!- 14 = 40,305
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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