document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=917000>Question 917000</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Bens grandfather was listening to the weather report which indicated that the maximum for the day was going to be 30C. He wants to know what the temperature is in F <BR>\n" );
document.write( "Using c/5 = (f-32)/2<BR>\n" );
document.write( "Someone had helped & had gotten<BR>\n" );
document.write( " 9/5(30)+32 <BR>\n" );
document.write( " 54+32<BR>\n" );
document.write( " f = 86<BR>\n" );
document.write( "I just don't get how we get the 9/5<BR>\n" );
document.write( "Help please? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #556474 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=556474\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are two main temperature scales:\r<BR>\n" );
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document.write( "°F, the Fahrenheit Scale (used in the US), and <BR>\n" );
document.write( "°C, the Celsius Scale (part of the Metric System, used in most other countries)\r<BR>\n" );
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document.write( "They both measure the same thing (temperature!), but use different numbers:<BR>\n" );
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document.write( "Boiling water (at normal pressure) measures <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=100 ALIGN=MIDDLE  ALT=\"100\"   DISABLED_style= \"max-width:90%; height:auto;\" >° in Celsius, but <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=212 ALIGN=MIDDLE  ALT=\"212\"   DISABLED_style= \"max-width:90%; height:auto;\" >° in Fahrenheit\r<BR>\n" );
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document.write( "And as water freezes it measures <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0 ALIGN=MIDDLE  ALT=\"0\"   DISABLED_style= \"max-width:90%; height:auto;\" >° in Celsius, but <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32 ALIGN=MIDDLE  ALT=\"32\"   DISABLED_style= \"max-width:90%; height:auto;\" >° in Fahrenheit.\r<BR>\n" );
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document.write( "The scales start at a different number (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0 ALIGN=MIDDLE  ALT=\"0\"   DISABLED_style= \"max-width:90%; height:auto;\" > vs <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32 ALIGN=MIDDLE  ALT=\"32\"   DISABLED_style= \"max-width:90%; height:auto;\" >), so we will need to add or subtract <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32 ALIGN=MIDDLE  ALT=\"32\"   DISABLED_style= \"max-width:90%; height:auto;\" >. \r<BR>\n" );
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document.write( "The scales rise at a different rate (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=100 ALIGN=MIDDLE  ALT=\"100\"   DISABLED_style= \"max-width:90%; height:auto;\" > vs <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=180 ALIGN=MIDDLE  ALT=\"180\"   DISABLED_style= \"max-width:90%; height:auto;\" >), so we will also need to multiply.\r<BR>\n" );
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document.write( "And so, to convert:\r<BR>\n" );
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document.write( "from Celsius to Fahrenheit: first multiply by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=180%2F100 ALIGN=MIDDLE  ALT=\"180%2F100\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then add <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32 ALIGN=MIDDLE  ALT=\"32\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "from Fahrenheit to Celsius: first subtract <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32 ALIGN=MIDDLE  ALT=\"32\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then multiply by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=100%2F180+ ALIGN=MIDDLE  ALT=\"100%2F180+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "But <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=180%2F100 ALIGN=MIDDLE  ALT=\"180%2F100\"   DISABLED_style= \"max-width:90%; height:auto;\" > can be simplified to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9%2F5 ALIGN=MIDDLE  ALT=\"9%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <BR>\n" );
document.write( "and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=100%2F180+ ALIGN=MIDDLE  ALT=\"100%2F180+\"   DISABLED_style= \"max-width:90%; height:auto;\" >can be simplified to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F9 ALIGN=MIDDLE  ALT=\"5%2F9\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so this is the easiest way:\r<BR>\n" );
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document.write( "°C to °F multiply by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9 ALIGN=MIDDLE  ALT=\"9\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then divide by<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5 ALIGN=MIDDLE  ALT=\"+5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then add <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32 ALIGN=MIDDLE  ALT=\"32\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "°F to °C deduct <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=32 ALIGN=MIDDLE  ALT=\"32\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then multiply by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5 ALIGN=MIDDLE  ALT=\"5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, then divide by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9 ALIGN=MIDDLE  ALT=\"9\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "We can write each as a formula like this: \r<BR>\n" );
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document.write( "Celsius to Fahrenheit: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28C+%2A+9%2F5%29+%2B+32+=+F ALIGN=MIDDLE  ALT=\"%28C+%2A+9%2F5%29+%2B+32+=+F\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Fahrenheit to Celsius: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28F+-32%29+%2A5%2F9+=+C ALIGN=MIDDLE  ALT=\"%28F+-32%29+%2A5%2F9+=+C\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so, you got<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28F+-32%29+%2A5%2F9+=+30 ALIGN=MIDDLE  ALT=\"%28F+-32%29+%2A5%2F9+=+30\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28F+-32%29+=+30%2A9%2F5 ALIGN=MIDDLE  ALT=\"%28F+-32%29+=+30%2A9%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F+-32+=+270%2F5 ALIGN=MIDDLE  ALT=\"F+-32+=+270%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F+-32+=+54 ALIGN=MIDDLE  ALT=\"F+-32+=+54\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F++=+54%2B32 ALIGN=MIDDLE  ALT=\"F++=+54%2B32\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F++=+86 ALIGN=MIDDLE  ALT=\"F++=+86\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " </SPAN>\n" );
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