document.write( "Question 1182241: Hello, I just need someone to check my answers for these questions. Thank You.\r
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document.write( "1. In how many different ways can seven books be arranged on a shelf of two particular books must always be next to each other?
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document.write( " for this I did 5! * 2! * 6 (5! from the 5 left over books and 2! from the two books, 6 positions for the girls to start with)\r
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document.write( "2. How many ways can five pieces of candy be divided between two children if each child receives at least one piece of candy?
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document.write( "There are two cases for this question.
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document.write( "1st case:
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document.write( "One child gets one candy, and they other one gets the rest. So
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document.write( "I did 5 choose 1 times 5 choose 4 which is 25 ways.\r
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document.write( "2nd case:
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document.write( "one child get 2 candies, while the other one get 3.
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document.write( "So I did 5 choose 2 times 5 choose 3, which is 100 ways.\r
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document.write( "Finally I add these values up 100 + 25 = 125\r
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document.write( "2. A team of five is to be chosen from a group of eight students. The two tallest students cannot both be on the team. How many different teams can be formed?
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document.write( " for this one, I did 8 choose 5 minus 6 choose 3 (because the two tallest are removed), which equals t0 56 - 20 = 36. \r
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document.write( "3. A group of 8 people consists of 6 adults and two children. Calculate the number of ways in which five people can be selected from these 8 in each of the cases:
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document.write( "(a)order of selection is unimportant
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document.write( "(b)the five people are selected in a definite order (I don't understand this one)
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document.write( "(c)order of selection is unimportant and at most one child may be selected.\r
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document.write( "for (a) I did 8 choose 5. 56 ways.
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document.write( "(b) I don't understand b at all
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document.write( "(c) I did 7 choose 4 because, one child is guaranteed to be selected. 35 ways.\r
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Algebra.Com's Answer #812206 by ikleyn(52788)![]() ![]() You can put this solution on YOUR website! .\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "In this my post, I will solve and explain you ONLY ONE problem of several posted.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "It is the problem n.2 about candies.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r\n" ); document.write( " In how many ways can five pieces of candy be divided between \r\n" ); document.write( " two children if each child receives at least one piece of candy?\r\n" ); document.write( "\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \r\n" ); document.write( "In this problem, candies are considered as NON-DISTINGUISHABLE - - - so the only difference \r\n" ); document.write( "between different cases is in the NUMBER of candies each child get.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Without going into high and complicated Math, we can write the FULL LIST of all possible solutions/answers\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " T A B L E\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " 1st child 2nd child\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " 1 4\r\n" ); document.write( "\r\n" ); document.write( " 2 3\r\n" ); document.write( "\r\n" ); document.write( " 3 2\r\n" ); document.write( "\r\n" ); document.write( " 4 1\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "It is the set of all possible different solutions.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "ANSWER. There are 4 (four) different solutions according to 4 different lines in the Table.\r\n" ); document.write( "\r \n" ); document.write( "\n" ); document.write( "Solved.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "////////////\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Please DO NOT POST many (more than one) PROBLEMS PER POST.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Post your problems SEPARATELY.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "It is the rule and the policy of this forum.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Each your problem/question requires to give you a small lesson/lecture, and \n" ); document.write( "if some tutor will answer everything in one piece, you will get a mess.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "It is why the requirement \"one problem per post\" is established.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Come again and enjoy my teaching ( ! )\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "\\\\\\\\\\\\\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "By the way, if the candies are considered as DISTINGUISHABLE in this problem, then the answer is 30:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " there are 30 different solutions in this case.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "30 = 32 -2; 32 = \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "(which the 1st child get; and then the 2nd child gets the rest just without a choice). \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "And we subtract 2 from 32 to exclude the degenerated (and prohibited) cases when one child gets 0 (zero) or all 5 candies.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |