document.write( "Question 1206503: Calculate the number of ways in which three girls and four boys can be seated on a row of seven chairs if each arrangement is to be symmetrical. \n" ); document.write( "
Algebra.Com's Answer #844035 by Edwin McCravy(20055)\"\" \"About 
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document.write( "A boy can't go in the middle, for that would leave an odd number of boys,\r\n" );
document.write( "3, to be divided to go on both sides of him, which would not be symmetrical.\r\n" );
document.write( "So 1 girl must go in the middle with 2 boys and 1 girl on each side of her.\r\n" );
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document.write( "To be symmetrical sex-wise, each arrangement must be in one of these 3 forms\r\n" );
document.write( "sex-wise:\r\n" );
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document.write( "GBBGBBG, BGBGBGB, or BBGGGBB\r\n" );
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document.write( "In each of those 3 forms, the girls can be arranged 3! ways, and the\r\n" );
document.write( "boys 4! ways: \r\n" );
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document.write( "So the answer is (3)(3!)(4!) = 432 ways.\r\n" );
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document.write( "Edwin
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