document.write( "Question 1203598: How many permutations of the letters {A, B, C , D, E , F , G } are
\n" ); document.write( "there, such that
\n" ); document.write( "1 A precedes B
\n" ); document.write( "2 A precedes B, and C precedes D
\n" ); document.write( "3 A precedes B, and B precedes C
\n" ); document.write( "4 C,D,E appear together in this order
\n" ); document.write( "5 A,B are appear together in this order, as do C , D \n" ); document.write( "

Algebra.Com's Answer #839269 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!
How many permutations of the letters {A, B, C , D, E , F , G } are
\n" ); document.write( "there, such that
\n" ); document.write( "1 A precedes B

That's the number of permutations of these 6 things AB, C, D, E, F, G\r\n" );
document.write( "taken all 6 at a time.

2 A precedes B, and C precedes D

That's the number of permutations of these 5 things AB, CD, E, F, G\r\n" );
document.write( "taken all 5 at a time.

3 A precedes B, and B precedes C

That's the number of permutations of these 5 things ABC, D, E, F, G\r\n" );
document.write( "taken all 5 at a time.

4 C,D,E appear together in this order

\r\n" );
document.write( "That's the number of permutations of these 5 things A, B, CDE, F, G\r\n" );
document.write( "taken all 5 at a time.

5 A,B appear together in this order, as do C,D.
\n" ); document.write( "

That's the number of permutations of these 5 things AB, CD, E, F, G\r\n" );
document.write( "taken all 5 at a time.\r\n" );
document.write( "\r\n" );
document.write( "You can calculate all these numbers of permutations yourself.  They're just\r\n" );
document.write( "factorials.\r\n" );
document.write( "\r\n" );
document.write( "Edwin

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