document.write( "Question 1114788: Hello, thank you for helping me with this math question
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document.write( "Consider a class with 12 girls and 10 boys (22 in total):
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document.write( "In how many ways can a committee of 5 consisting of 3 girls and 2 boys be chosen?
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document.write( "a) 0.03
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document.write( "b) 792
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document.write( "c) 0.3759
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document.write( "d) 9900
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document.write( "Here is my thought process which led to none of the given answer choices.
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document.write( "We can easily eliminate A and C, as they are not numbers of different arrangements, rather, they are probabilities, which is not what the question is asking.
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document.write( "I recognized the nature of the question to be a permutation, as you care about which order you are placing the 12 girls in 3 places on the committee. For example, Girl A, B, C is a possible permutation, but B, A, C is also a different permutation that must be counted. The same is true for putting the 10 boys into the 2 other spaces on the committee. So, I tried (12 nPr 3) + (10 nPr 2), which made logical sense in my head as you want 12 girls in 3 different ways on the committee plus the 10 boys you want in 3 different ways on the committee.
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document.write( "This way gets you to an answer of 1410, which is way off from the answer choices,so I was wondering what I did wrong in this thought process.
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document.write( "Thank you for your time and free advice :)
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Algebra.Com's Answer #729703 by greenestamps(13200)![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "(1) It is NOT a permutation; on a committee the order is NOT important. \n" ); document.write( "(2) For each of the ways of choosing 3 of the 12 girls there are many ways of choosing 2 of the 10 boys. That \"for each\" means you need to multiply the two numbers together -- not add them. \n" ); document.write( "Fix those two parts of your analysis of the problem and you should reach answer d. \n" ); document.write( " |