document.write( "Question 1187928: There are 19 animals in the field. Some are goats and some are ducks. There are 72 legs in all. How many of each animal are in the field?\r
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Algebra.Com's Answer #818943 by ikleyn(52790) $\"\"$ $\"About$

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\n" ); document.write( "There are 19 animals in the field. Some are goats and some are ducks.
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document.write( "Let x be the number of goats;  then the number of ducks is (19-x).\r\n" );
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document.write( "There is no need to remind that the ducs have two legs, while the goats have four legs.\r\n" );
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document.write( "So we write an equation for the total of legs\r\n" );
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document.write( "    4x + 2*(19-x) = 72.\r\n" );
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document.write( "Simplify and find x\r\n" );
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document.write( "    4x + 38 - 2x = 72\r\n" );
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document.write( "    4x - 2x = 72 - 38\r\n" );
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document.write( "      2x    =   34\r\n" );
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document.write( "       x    =   34/2 = 17.\r\n" );
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document.write( "ANSWER.  There are 17 goats and 19-17 = 2 ducks.\r\n" );
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document.write( "CHECK.   17*4 + 2*2 = 68 + 4 = 72  total legs.   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "To see many other similar (and different) solved problems, look into the lessons\r
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