document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=615859>Question 615859</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I do not know where to start with this problem:\r<BR>\n" );
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document.write( "A compass and a ruler together cost $4. The compass costs .90 more than the ruler. How much does the compass cost?\r<BR>\n" );
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document.write( "I am 53 and have never understood how to do word problems. I can solve the equations but cannot come up with the equation itself. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #387337 by </B><A HREF=/tutors/aboutme.mpl?userid=dragonwalker><B>dragonwalker(73)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=dragonwalker><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=387337\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The key to coming up with a formula is to look at the first unknown and then the relationship between the unknowns.\r<BR>\n" );
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document.write( "We don't know the cost of either but we DO know that one costs more than the other and we know the difference.\r<BR>\n" );
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document.write( "We want to know how much the compass costs so let us give that value the letter 'a'\r<BR>\n" );
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document.write( "So if the compass costs 'a' then the ruler costs 0.90 less which can be simply written as a - 0.90\r<BR>\n" );
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document.write( "We know that the cost of both is $4.00 so:\r<BR>\n" );
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document.write( "we add 'a' (the cost of the compass) to a - 0.90 (the cost of the ruler).\r<BR>\n" );
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document.write( "So:\r<BR>\n" );
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document.write( "a + a - 0.90 = 4.00\r<BR>\n" );
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document.write( "rearrange:\r<BR>\n" );
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document.write( "a + a = 4.00 + 0.90 <BR>\n" );
document.write( "2a = 4.90<BR>\n" );
document.write( "a = 2.45\r<BR>\n" );
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document.write( "So the cost of the compass is $2.45\r<BR>\n" );
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document.write( "If you want to check you can find from this that the ruler costs 90c less so costs $1.55\r<BR>\n" );
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document.write( "Add them together:<BR>\n" );
document.write( "1.55 + 2.45 = 4.00 !!!!\r<BR>\n" );
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document.write( "Hope this helps...\r<BR>\n" );
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document.write( " </SPAN>\n" );
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