document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=159670>Question 159670</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0395977258/algebrahomeworkh>Algebra and Trigonometry Structure and Method book 2</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> I have been struggling to figure out this problem and I was wondering if someone could help me? Please and Thank You!! I would deeply appreciate it!!\r<BR>\n" );
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document.write( "Problem Solving: Using Systems<BR>\n" );
document.write( "An overseas phone call is charged at one rate (a fixed amount) for the first minute and at a different rate for each additional minute. If a 7 min call costs $10, and a 4 min call costs $6.40, find each rate. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #117727 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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/cgi-bin/show-face.mpl?user=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=117727\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An overseas phone call is charged at one rate (a fixed amount) for the first minute and at a different rate for each additional minute. If a 7 min call costs $10, and a 4 min call costs $6.40, find each rate.<BR>\n" );
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document.write( "Let F = fixed rate<BR>\n" );
document.write( "and R = additional minutes rate<BR>\n" );
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document.write( "Because we have two unknowns, we'll need two equations.  <BR>\n" );
document.write( "Our first equation comes from \"a 7 min call costs $10\"<BR>\n" );
document.write( "F + 7R = 10<BR>\n" );
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document.write( "Our second equation comes from \"a 4 min call costs $6.40\"<BR>\n" );
document.write( "F + 4R = 6.40<BR>\n" );
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document.write( "Subtracting equation 2 from equation 2:<BR>\n" );
document.write( " F + 7R = 10<BR>\n" );
document.write( "-F - 4R = -6.40<BR>\n" );
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document.write( "     3R = 3.60<BR>\n" );
document.write( "R = $1.20 <BR>\n" );
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document.write( "To find F, substitute the above into equation 1 and solve:<BR>\n" );
document.write( "F + 7R = 10<BR>\n" );
document.write( "F + 7(1.20) = 10<BR>\n" );
document.write( "F + 8.4 = 10<BR>\n" );
document.write( "F = $1.60<BR>\n" );
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document.write( "Therefore:<BR>\n" );
document.write( "Fixed rate is $1.60<BR>\n" );
document.write( "Per minute charge after the first min is $1.20<BR>\n" );
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