document.write( "Question 1066088: In a 10-item Mathematics problem-solving test, how many ways can you select 5 problems to solve? How many ways can you select the 5 questions if you are required to answer question number 10? \n" ); document.write( "
Algebra.Com's Answer #681467 by swincher4391(1107)![]() ![]() You can put this solution on YOUR website! Part a)\r \n" ); document.write( "\n" ); document.write( "Since it appears that the order does not matter (we are just choosing any 5 at once), then we are using a combination. A couple of different ways to compute this.\r \n" ); document.write( "\n" ); document.write( "You can use the nCr button on your calculator, but I will do it using the formula.\r \n" ); document.write( "\n" ); document.write( "So nCr = \n" ); document.write( "\n" ); document.write( "We are finding 10 C 5 = \n" ); document.write( "\n" ); document.write( "10! is quite large, so let's try to do some simplification.\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "and 3 * 2* 7 * 6 is \n" ); document.write( "\n" ); document.write( "---------------------------------------------- \n" ); document.write( "Part b)\r \n" ); document.write( "\n" ); document.write( "10 is fixed so we really only have 9 questions and we are choosing 4.\r \n" ); document.write( "\n" ); document.write( "So 9 C 4 = \r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So 3 * 7 * 6 = \n" ); document.write( "\n" ); document.write( "------------------------------------ \n" ); document.write( "Finally, Google will do it for you as well.\r \n" ); document.write( "\n" ); document.write( "10 choose 5 : https://www.google.com/#q=10+choose+5\r \n" ); document.write( "\n" ); document.write( "9 choose 4 : https://www.google.com/#q=9+choose+4 \n" ); document.write( " \n" ); document.write( " |