document.write( "Question 1150617: In Tae Kwon Do class, 40% of the students are boys. There are 18 fewer boys than girls. How many students are in the Tae Kwon Do class altogether? \n" ); document.write( "

Algebra.Com's Answer #772005 by VFBundy(438) $\"\"$ $\"About$

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Number of girls = x
\n" ); document.write( "Number of boys = x - 18
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\n" ); document.write( " $\"%28x+-+18%29%2F%28x+%2B+%28x+-+18%29%29\"$ = 0.4
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\n" ); document.write( " $\"%28x+-+18%29%2F%282x+-+18%29%29\"$ = 0.4
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\n" ); document.write( "Cross-multiply:
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\n" ); document.write( "x - 18 = 0.4(2x - 18)
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\n" ); document.write( "x - 18 = 0.8x - 7.2
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\n" ); document.write( "0.2x = 10.8
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\n" ); document.write( "x = 54
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\n" ); document.write( "Number of girls = x = 54
\n" ); document.write( "Number of boys = x - 18 = 54 - 18 = 36
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\n" ); document.write( "There are 54 girls in the class and 36 boys in the class. Therefore, there are 90 students in the class altogether. \n" ); document.write( "

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