document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=919961>Question 919961</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Students were asked to write an algebraic expression for the sum of three consecutive natural numbers. One student wrote<BR>\n" );
document.write( "x + (x + 1) + (x + 2) = 3x + 3. Another wrote (x - 1) + x + (x + 1) = 3x. Explain who is correct and why. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #558072 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=558072\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The only trouble I can find is that the natural numbers start at 1.  The second version, if x itself is 1, would have one of the numbers to be summed, x-1 NOT a natural number, because 1-1=0, which is acceptable for WHOLE numbers, but not for NATURAL numbers.  \r<BR>\n" );
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document.write( "The first version, 3x+3, is acceptable.  Each of the three consecutive numbers will be Natural if x is chosen among the Natural numbers. </SPAN>\n" );
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