document.write( "Question 251091: 5 people (A,B,C,D,E)sit together in a theater. How many ways can they be arranged if personB is seated to the right of, but not necessarily next to, personC???
\n" ); document.write( "How would you figure this out????
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Algebra.Com's Answer #184199 by palanisamy(496)\"\" \"About 
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5 people (A,B,C,D,E)sit together in a theater.
\n" ); document.write( "Total number of arrangements = 5P5 = 5!
\n" ); document.write( "First let us consider the case in which C occupies the left extreme seat.
\n" ); document.write( "The other four people can be arranged in 4P4 = 4!= 1x2x3x4 = 24 ways.\r
\n" ); document.write( "\n" ); document.write( " Next, let C occupy the second seat.
\n" ); document.write( "Excluding B, the first seat can be filled by either one of A,D,E in 3 ways and the other 3 seats can be filled in 3! ways.
\n" ); document.write( "So, total number of ways = 3x3! = 3x3x2x1 = 18\r
\n" ); document.write( "\n" ); document.write( " Next,let C occupy the third seat.
\n" ); document.write( "Excluding B, the first two seats can be filled by either one of A,D,E in
\n" ); document.write( "3P2 = 6 ways and the other 2 seats can be filled in 2! ways.
\n" ); document.write( "So, total number of ways = 6x2! = 6x2x1 = 12\r
\n" ); document.write( "\n" ); document.write( " Next,let C occupy the fourth seat.
\n" ); document.write( "Excluding B, the first three seats can be filled by either one of A,D,E in
\n" ); document.write( "3P3 = 3! ways and the other last seat can be filled by B in 1 way
\n" ); document.write( "So, total number of ways = 3!x1 =3x2x1x1 = 6\r
\n" ); document.write( "\n" ); document.write( "So the total number of ways in which B sits right of C is = 24+18+12+6 =60 \r
\n" ); document.write( "\n" ); document.write( "ANOTHER METHOD
\n" ); document.write( "5 people (A,B,C,D,E)sit together in a theater.
\n" ); document.write( "Total number of arrangements = 5P5 = 5!
\n" ); document.write( "There are only two possible ways.
\n" ); document.write( "Either B can sit to the right of C or B can sit to the left of C.
\n" ); document.write( "The number of ways are equal in both cases.
\n" ); document.write( "Therefore the total number of ways in which B sits right of C is = 5! / 2
\n" ); document.write( " =1*2*3*4*5/2 =60
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