document.write( "Question 1135887: jack is jill brother.jill has as many brother as sister. jack has twice mas many sisters as brothers . how many children are there in the family? \n" ); document.write( "

Algebra.Com's Answer #753588 by ikleyn(52810) $\"\"$ $\"About$

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\n" ); document.write( " $\"highlight%28cross%28jack%29%29\"$ Jack is $\"highlight%28cross%28jill%29%29\"$ Jill's brother.
\n" ); document.write( "jill has as many $\"highlight%28cross%28brother%29%29\"$ brothers as $\"highlight%28cross%28sister%29%29\"$ sisters.
\n" ); document.write( "jack has twice $\"highlight%28cross%28mas%29%29\"$ as many sisters as brothers.
\n" ); document.write( "how many children are there in the family?
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document.write( "Jack is a boy; Jill is a girl   (If to follow to commonly accepted way of using English names).\r\n" );
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document.write( "Let b = number of boy children in the family\r\n" );
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document.write( "    g = --------- girl  - - - - - - - - - - \r\n" );
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document.write( "The condition says\r\n" );
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document.write( "    g-1 = b         (1)     (\"Jill has as many brother as sister\")\r\n" );
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document.write( "    2*(b-1) = g    (2)     (\"Jack has twice as many sisters as brothers \")\r\n" );
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document.write( "From equation (1), substitute  b = g-1  into equation (2).\r\n" );
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document.write( "    2*(g-2) = g\r\n" );
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document.write( "    2g - 4 =  g    =====>  g = 4.\r\n" );
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document.write( "ANSWER.  There are 4 girls and 3 boys in the family. In total, 7 children.\r\n" );
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\n" ); document.write( "\n" ); document.write( "See the lesson\r
\n" ); document.write( "\n" ); document.write( " - Classic entertainment problems, Problem 5\r
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