document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=220726>Question 220726</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This is a word problem my son just had on a quiz and I couldn't solve either. I thought we didn't have enough info.\r<BR>\n" );
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document.write( "Marshfield Middle school cluster C has 100 students in honors pre-algebra<BR>\n" );
document.write( "Cluster C has 30 students enrolled in after school math enrichment.\r<BR>\n" );
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document.write( "If 105 cluster C students are in only one or the other of these, how many students are in both?\r<BR>\n" );
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document.write( "Tried a venn diagram to get my mind around it, didn't work. (I keep thinking I need to know the total enrollment of honors pre-alg plus after school)my son said he got 12.5 as an answer, but the teacher said it would come out as a whole number.<BR>\n" );
document.write( "Thanks, Trish  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #165625 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=165625\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let \r<BR>\n" );
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document.write( "x = Number of students in both classes\r<BR>\n" );
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document.write( "To find the number of students in only one or the other (not both) class, we subtract out the number that are in both (which is 'x') from the total.\r<BR>\n" );
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document.write( "In other words, \r<BR>\n" );
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document.write( "Number that are in one or other (not both) = (Number in pre-algebra + Number in math enrichment) - (Number in both) \r<BR>\n" );
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document.write( "105 = (100+30) - x\r<BR>\n" );
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document.write( "105 = 130 - x\r<BR>\n" );
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document.write( "105-130 = - x\r<BR>\n" );
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document.write( "- 25 = - x\r<BR>\n" );
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document.write( "25 = x\r<BR>\n" );
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document.write( "x = 25\r<BR>\n" );
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document.write( "So there are 25 students in both classes.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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