document.write( "Question 1183995: Valentina, Luke, Sally, Han and Mae are to be placed in a line in random order.\r
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document.write( "What is the probability that the boys will be next to each other and the girls will all be next to each other? \n" );
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Algebra.Com's Answer #814522 by Theo(13342)![]() ![]() You can put this solution on YOUR website! the possible arrangements, without any restrictions, are 5! = 120. \n" ); document.write( "if the boys need to be together, that can happen in 3! arrangements = 6. \n" ); document.write( "if the girls need to be together, that can happen in 2! arrangements = 2. \n" ); document.write( "that would be a total of 6 * 2 = 12 possible arrangements if all the boys are on the left and another total of 2 * 6 = 12 possible arrangements if all the girls are on the left. \n" ); document.write( "you get 24 possible arrangements out of 120 possible arrangements, giving you a probability of 24/120 = 1/5.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "let the boys be 1,2,3. \n" ); document.write( "let the girls be a,b.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "when the girls are on the left, you get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "ab123 \n" ); document.write( "ab132 \n" ); document.write( "ab213 \n" ); document.write( "ab231 \n" ); document.write( "ab312 \n" ); document.write( "ab321\r \n" ); document.write( "\n" ); document.write( "ba123 \n" ); document.write( "ba132 \n" ); document.write( "ba213 \n" ); document.write( "ba231 \n" ); document.write( "ba312 \n" ); document.write( "ba321\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "that's a total of 12.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "when boys are on the left and the girls are on the right, that's another 12 possible arrangements, for a total of 24 out of 120 = 1/5.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "as far as i can tell, the probability is 1/5.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |