document.write( "Question 481474: pls help me solve this problem in probability... thank you..\r
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\n" ); document.write( "\n" ); document.write( "a ring of keys can hold 7 keys. In how many ways can the keys be arranged if the ring can be turned over?
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Algebra.Com's Answer #329704 by Theo(13342)\"\" \"About 
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ring of keys can hold 7 keys.
\n" ); document.write( "the keys are a,b,c,d,e,f,g
\n" ); document.write( "the possible number of arrangements would be 7! = 7*6*5*4*3*2*1 = 5040.
\n" ); document.write( "let's see what happens if there are only 3 keys.
\n" ); document.write( "the number of arrangements would be 3! = 3*2 = 6
\n" ); document.write( "those arrangements would be:
\n" ); document.write( "a,b,c
\n" ); document.write( "a,c,b
\n" ); document.write( "b,a,c
\n" ); document.write( "b,c,a
\n" ); document.write( "c,a,b
\n" ); document.write( "c,b,a
\n" ); document.write( "if you turn the ring over, then:
\n" ); document.write( "a,b,c becomes c,b,a
\n" ); document.write( "a,c,b becomes b,c,a
\n" ); document.write( "b,a,c becomes c,a,b
\n" ); document.write( "b,c,a becomes a,c,b
\n" ); document.write( "c,a,b becomes b,a,c
\n" ); document.write( "c,b,a becomes a,b,c
\n" ); document.write( "since all these arrangements are already accounted for, there are no new arrangements that are created by flipping the ring over.
\n" ); document.write( "i would say that you get the same number of ways the keys can be arranged whether or not the ring can be turned over.
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