document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=206048>Question 206048</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help on making a system of equations based on a word problem. Here is the problem: Tricia and Michael share a cell phone plan, together; they made a total of 52 calls last month for a total of 620 minutes. Tricia averaged 15 minutes for each of her calls, while Michael averaged 10 minutes.\r<BR>\n" );
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document.write( "-How many calls did Tricia make last month?\r<BR>\n" );
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document.write( "-How many calls did Michael make last month?\r<BR>\n" );
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document.write( "Thank you for help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #155612 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=155612\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Tricia and Michael share a cell phone plan, together; they made a total of 52 calls last month for a total of 620 minutes. Tricia averaged 15 minutes for each of her calls, while Michael averaged 10 minutes. <BR>\n" );
document.write( "-How many calls did Tricia make last month?<BR>\n" );
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document.write( "-How many calls did Michael make last month? \r<BR>\n" );
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document.write( "Equations: <BR>\n" );
document.write( "Quantity Eq.::: t + m = 52<BR>\n" );
document.write( "Time Eq:::::::15t + 10m = 620<BR>\n" );
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document.write( "Multiply thru the 1st to set it up for elimination:<BR>\n" );
document.write( "15t + 15m = 15*52<BR>\n" );
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document.write( "Subtract the 2nd equation from that and solve for \"m\":<BR>\n" );
document.write( "5m = 15*52-620<BR>\n" );
document.write( " m = 32 (# of calls Michael made)<BR>\n" );
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document.write( "Substitute into t+m=52 to solve for \"t\":<BR>\n" );
document.write( "t + 32 = 52<BR>\n" );
document.write( "t = 20 (# of calls Tricia made)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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