document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=934868>Question 934868</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a class of 31 students , 22 study physics , 20 study chemistry & 5 study neither,  how many students in the class study both  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #567933 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=567933\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In a class of 31 students , 22 study physics , 20 study chemistry & 5 study neither, how many students in the class study both <BR>\n" );
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document.write( "Draw a Venn Diagram with 2 intersecting circles labeled physics and chemistry.<BR>\n" );
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document.write( "Let \"x\" be the number who study both::<BR>\n" );
document.write( "Put \"x\" in the intersection of the 2 circles.<BR>\n" );
document.write( "Then 22-x = # who study physics but not chem.<BR>\n" );
document.write( "And 20-x = # who study chem and not physics.<BR>\n" );
document.write( "Note: 5 are in the rectangle but not in either circle.<BR>\n" );
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document.write( "Equation:<BR>\n" );
document.write( "# in circles:: 22-x + 20-x + x = 31-5<BR>\n" );
document.write( "42-x = 36<BR>\n" );
document.write( "x = 6 (# in the class who study both)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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