document.write( "Question 1169916: There are 2 Senators from each of 50 states. We wish to make a 3-Senator committee in which no two members are from the same state. How many ways can the 3-Senator committee be formed such that no two Senators are from the same state? \n" ); document.write( "
Algebra.Com's Answer #794763 by math_tutor2020(3817)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "There are three slots or seats to fill on this committee.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "For the first slot, we have 100 choices since we have 2*50 = 100 senators. \n" ); document.write( "After that person is picked, there are 98 choices left. Why 98 and not 99? Because we cannot pick a senator from the same state as the first person selected.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "For example, let's say we pick a senator from Michigan to fill the first seat. The other senator from Michigan cannot be selected if we want this three-person committee to not have two members from the same state.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "So again we have 98 choices for the second slot.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Then whoever goes in the second slot will lower the amount of choices down to 96 for similar reasoning as before.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Overall we have 100*98*96 = 940,800 permutations possible \r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Since order doesn't matter, we divide by 3! = 3*2*1 = 6 to get (940,800)/6 = 156,800\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Note how there are 6 ways to arrange a group of three items \n" ); document.write( "{A,B,C} \n" ); document.write( "{A,C,B} \n" ); document.write( "{B,A,C} \n" ); document.write( "{B,C,A} \n" ); document.write( "{C,A,B} \n" ); document.write( "{C,B,A} \n" ); document.write( "All six sets listed above are the same set since all have A,B,C in some order. The order doesn't matter on a committee. No member outranks another. All that matters is the group overall.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Answer: 156,800 \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |