document.write( "Question 1149800: Hi\r
\n" ); document.write( "\n" ); document.write( "the average mass of a group of people was 42kg at first. When one person weight 70kg joined the average mass became 46kg. How man people were in the group at first.\r
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Algebra.Com's Answer #771145 by ikleyn(52810) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Let the number under the question is \"n\".\r\n" );
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document.write( "Then the total mass of \"n\" people is  42*n kilograms.\r\n" );
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document.write( "When the 70-kilo person was added to the group, the mass became  (42*n+70) kilograms;\r\n" );
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document.write( "the number of people in the extended group is (n+1) now.\r\n" );
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document.write( "So your equation is\r\n" );
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document.write( "     = 46.\r\n" );
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document.write( "To solve the equation, first multiply both sides by (n+1).  You will get\r\n" );
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document.write( "    42*n + 70 = 46*(n+1).\r\n" );
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document.write( "The rest is clear, and I leave it to you to complete the solution on your own.\r\n" );
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\n" ); document.write( "\n" ); document.write( "To see many other similar solved problems, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on average scores, weight, height and temperature\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on average scores\r
\n" ); document.write( "\n" ); document.write( "    - Solved problems on average age \r
\n" ); document.write( "\n" ); document.write( "    - Miscellaneous problems on average values \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Consider these lessons as your textbook, handbook, tutorials and (free of charge) home teacher.\r
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\n" ); document.write( "\n" ); document.write( "If you still have questions or difficulties, let me know.\r
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\n" ); document.write( "\n" ); document.write( "If you will write to me, then refer to the problem's ID number, which is 1149800.\r
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\n" ); document.write( "\n" ); document.write( "Otherwise, I will not know to whom to answer.\r
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\n" ); document.write( "\n" ); document.write( "Good luck (!)\r
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