document.write( "Question 218176: Kindly answer this question please!!! Thanks!! In how many ways 4 people be seated in a row of 6 chairs if A.they can be seated anywhere B. the empty chairs are adjacent to each other? \n" ); document.write( "
Algebra.Com's Answer #164339 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
4 people 6 chairs
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\n" ); document.write( "sitting anywhere, the number is 15.
\n" ); document.write( "if the empty chairs have to be adjacent, the number is 5
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\n" ); document.write( "let's do adjacent first.
\n" ); document.write( "you have 6 chairs and 4 people.
\n" ); document.write( "that means 2 empty chairs.
\n" ); document.write( "if they have to be together, they become equivalent to 1 empty chair with the total number of chairs being 5.
\n" ); document.write( "you now have 5 chairs and one of them has to be empty.
\n" ); document.write( "this can happen in 5 ways.
\n" ); document.write( "you get:
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\n" ); document.write( "no other combination is possible.
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\n" ); document.write( "general formula for number of combinations is:
\n" ); document.write( "n! / ((x)!*(n-x)!)
\n" ); document.write( "formula for this problem is 5! / (1!*4!)
\n" ); document.write( "where:
\n" ); document.write( "1! represents x!
\n" ); document.write( "4! represents (n-x)!
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\n" ); document.write( "the first part of your problem is solved as follows:
\n" ); document.write( "you have 6 slots.
\n" ); document.write( "you can fill them with 4 people
\n" ); document.write( "that will leave 2 empty slots.
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\n" ); document.write( "the general formula for number of possible combinations of 4 out of 6 is once again n! / ((x)!*(n-x)!)
\n" ); document.write( "This becomes 6! / (2!*4!)
\n" ); document.write( "where:
\n" ); document.write( "n = 6
\n" ); document.write( "x = 2
\n" ); document.write( "n-x = 4
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\n" ); document.write( "The answer is 6*5*4*3*2*1 / 2*1*4*3*2*1 30/2 = 15
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\n" ); document.write( "there are 15 combinations possible.
\n" ); document.write( "They are:
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\n" ); document.write( "fefeff
\n" ); document.write( "feffef
\n" ); document.write( "fefffe
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\n" ); document.write( "You have 15 ways in which you can fill the 6 seats with 4 people assuming they can sit anywhere they want.
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\n" ); document.write( "You have 5 ways in which you can fill the 6 seats with 4 people assuming the empty seats have to be together.
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