document.write( "Question 832636: A class has 30-40 students. Each boy in the class bring 15 chocolate bars fcr a class party to celebrate Teacher's Day. The chocolate bars are shared equally among the 20 girls of the class and their form teacher with no leftoversx.
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Algebra.Com's Answer #513717 by Edwin McCravy(20056) $\"\"$ $\"About$

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A class has 30-40 students. Each boy in the class bring 15 chocolate bars fcr a class party to celebrate Teacher's Day. The chocolate bars are shared equally among the 20 girls of the class and their form teacher with no leftovers.
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document.write( "There are between 30 and 40 students,\r\n" );
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document.write( "There are 20 girls.  Therefore \r\n" );
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document.write( "There are between 10 and 20 boys.\r\n" );
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document.write( "Since each boy brought 15 chocolate bars,\r\n" );
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document.write( "So there are between 150 and 300 chocolate bars, and\r\n" );
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document.write( "therefore, the number of chocolate bars is a multiple of 15.\r\n" );
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document.write( "The chocolate bars are shared equally among 21 people (the girls\r\n" );
document.write( "and the teacher) with no leftovers.\r\n" );
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document.write( "Therefore the number of bars is also a multiple of 21.\r\n" );
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document.write( "Therefore the number of chocolate bars is a multiple of the\r\n" );
document.write( "least common multiple of 15 and 21 which is 105.  So there\r\n" );
document.write( "are 105k chocolate bars for some positive integer k, and since \r\n" );
document.write( "the number of chocolate bars is between 150 and 300,\r\n" );
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document.write( "       150 ≦ 105k ≦ 300\r\n" );
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document.write( "Divide all three parts by 105\r\n" );
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document.write( "1.428571429 ≦ k ≦ 2.857142857\r\n" );
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document.write( "So        2 ≦ k ≦ 2\r\n" );
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document.write( "Therefore k = 2\r\n" );
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document.write( "Therefore, there are 105k = 105(2) = 210 chocolate bars.\r\n" );
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document.write( "Since every boy brought 15, there are 210÷15 = 14 boys\r\n" );
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document.write( "Since there are 20 girls and 14 boys, there are \r\n" );
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document.write( "20+14 = 34 students in the class.\r\n" );
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document.write( "Since every girl and the teacher shared the 210 chocolate bars,\r\n" );
document.write( "every girl and the form teacher received 210÷21 = 10 chocolate\r\n" );
document.write( "bars.\r\n" );
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document.write( "Solution: 34 students in the class.  The form teacher received\r\n" );
document.write( "10 chocolate bars.\r\n" );
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document.write( "Edwin

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