document.write( "Question 1101050: A teacher makes a multiple-choice quiz with 12 questions. 3 answers are A, 3 answers are B,2 answers are C and 4 answers are D. How many possible answer keys are possible\r
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document.write( "I think you can solve it like this but am not sure:\r
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document.write( "12C3 x 9C3 x 6C2 x 4C4
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document.write( "= 277200 keys \n" );
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Algebra.Com's Answer #715709 by rothauserc(4718)![]() ![]() You can put this solution on YOUR website! for this problem, we use combinatorial counting\r \n" ); document.write( "\n" ); document.write( "for the first question there are 12 possible choices, for the second question there are 11 choices, for the third question there are 10 possible choices, ... \n" ); document.write( ": \n" ); document.write( "Note that I assume there are NO restrictions on the placement of the answers \n" ); document.write( ": \n" ); document.write( "12! = 479001600 \n" ); document.write( ": \n" ); document.write( "now we must divide 479001600 by the number of permutations we can not distinguish \n" ); document.write( ": \n" ); document.write( "************************************************************* \n" ); document.write( "479001600 / (3! * 3! * 2! * 4!) = 277200 possible answer keys \n" ); document.write( "************************************************************* \n" ); document.write( ": \n" ); document.write( " \n" ); document.write( " |