vasoolraja Posted December 9, 2008 Share Posted December 9, 2008 I would really appreciate if someone would show me the steps to answer this question: Martha invited 4 friends to go with her to the movies. There are 120 different ways in which they can sit together in a row. In how many of those ways is Martha sitting in the middle? Quote Link to comment Share on other sites More sharing options...
bkc Posted December 9, 2008 Share Posted December 9, 2008 Imo 24 Quote Link to comment Share on other sites More sharing options...
vasoolraja Posted December 9, 2008 Author Share Posted December 9, 2008 The answer is 24; I would like to know how you arrived at the answer. Please show me the steps. Thanks! Quote Link to comment Share on other sites More sharing options...
kkaman Posted December 9, 2008 Share Posted December 9, 2008 I would really appreciate if someone would show me the steps to answer this question: Martha invited 4 friends to go with her to the movies. There are 120 different ways in which they can sit together in a row. In how many of those ways is Martha sitting in the middle? 5!=120, so there are 5 seats. Martha is in the middle seat. Arrange the reamainig 4 people. First place can be filled in 4 ways. second place in 3 ways and so on.......4*3*2*1=24 Hope its clear? Quote Link to comment Share on other sites More sharing options...
vasoolraja Posted December 9, 2008 Author Share Posted December 9, 2008 5!=120, so there are 5 seats. Martha is in the middle seat. Arrange the reamainig 4 people. First place can be filled in 4 ways. second place in 3 ways and so on.......4*3*2*1=24 Hope its clear? Thanks for your response kkaman! I fine permutation combination problems very tough. Could you please suggest me a way to conquer this section? Thanks! Quote Link to comment Share on other sites More sharing options...
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