document.write( "Question 585373: Martha entered the elevator and went down 7 floors, up 10 floors, up two floors, then down five floors. She was on the eleventh floor. What floor did she enter the elevator? \n" ); document.write( "
Algebra.Com's Answer #373303 by jim_thompson5910(35256)\"\" \"About 
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\"went down 7 floors\" ---> -7
\n" ); document.write( "\"up 10 floors\" ---> +10
\n" ); document.write( "\"up two floors ---> +2
\n" ); document.write( "\"down five floors\" --> -5\r
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\n" ); document.write( "\n" ); document.write( "Add up the figures to get: -7 + 10 + 2 + (-5) = 0\r
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\n" ); document.write( "\n" ); document.write( "So her net change is 0 floors (ie after all that, she hasn't gone up or down). Therefore, if she ended on the 11th floor, this must mean she started on the 11th floor.\r
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