document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=45866>Question 45866</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the element europium (EU) exists in nature as two isotopes: (151 EU)with a mass of 150.9196 amu & (153 EU) with a mass of 152.9209 amu. The average mass of EU is 151.96 How do you calculate the relative abundance of the two EU isotopes?  X% times 150.9196 (plus) Y% times 152.9209 equals = 151.96. what are the X and Y percentages? And what is the formula to identify the unknowns X and Y?    </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #30452 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=30452\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How do you calculate the relative abundance of the two EU isotopes? X% times 150.9196 (plus) Y% times 152.9209 equals = 151.96. what are the X and Y percentages?\r<BR>\n" );
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document.write( "Let the percentages be respectively x and y, as you have indicated.<BR>\n" );
document.write( "EQUATIONS:<BR>\n" );
document.write( "1st: x+y=100% = 1<BR>\n" );
document.write( "2nd: 150.9196x + 152.9209y = 151.96\r<BR>\n" );
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document.write( "Solve this using substitution.<BR>\n" );
document.write( "I get x= 48.01% and y=51.99%\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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