document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1033632>Question 1033632</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Nick has 2 cars.<BR>\n" );
document.write( "Car A uses petrol.<BR>\n" );
document.write( "Car B uses diesel.\r<BR>\n" );
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document.write( "Petrol costs £1.39 per litre.<BR>\n" );
document.write( "Diesel costs £1.47 per litre.\r<BR>\n" );
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document.write( "Below shows the average distance that Nick can drive each using 1 litre of fuel:<BR>\n" );
document.write( "Car A- 10.3 miles per litre of petrol<BR>\n" );
document.write( "car B- 14.6 miles per litre of diesel\r<BR>\n" );
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document.write( "Nick is going on a journey in one of his cars.<BR>\n" );
document.write( "The distance Nick is going to drive is 450 miles.<BR>\n" );
document.write( "Work out the difference of the total costs of the fuel for the 2 cars for this journey.\r<BR>\n" );
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document.write( "What I Did:(Question is out of 4 marks and i got only 2)\r<BR>\n" );
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document.write( "CAR A:<BR>\n" );
document.write( "£1.39 per litre<BR>\n" );
document.write( "10.3 miles.<BR>\n" );
document.write( "450 miles/ 10(estimate)= 45\r<BR>\n" );
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document.write( "CAR B:<BR>\n" );
document.write( "£1.49 per litre<BR>\n" );
document.write( "14.6 miles<BR>\n" );
document.write( "450 miles/15(estimate)=30\r<BR>\n" );
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document.write( "SO then I did:<BR>\n" );
document.write( "1.50*30=£45\r<BR>\n" );
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document.write( "63-45=18<BR>\n" );
document.write( "so I got £18 as the answer<BR>\n" );
document.write( "Where did I lose the 2 marks? Please help me </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #648424 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=648424\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "the question did not say to estimate.<BR>\n" );
document.write( "the questions said what is the difference.<BR>\n" );
document.write( "you're probably close, but you're certainly not right on.\r<BR>\n" );
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document.write( "let's see what the answer would be if we didn't round the intermediate results.\r<BR>\n" );
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document.write( "petrol car costs 1.39 per liter and gets 10.3 miles per liter.<BR>\n" );
document.write( "diesel car costs 1.47 per liter and gets 14.6 miles per liter.\r<BR>\n" );
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document.write( "distance traveled is 450 miles.\r<BR>\n" );
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document.write( "cost for petrol car is 450 / 10.3 * 1.39 = 60.72815534 pounds.<BR>\n" );
document.write( "cost for diesel car is 450 / 14.6 * 1.47 = 45.30821918 pounds.\r<BR>\n" );
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document.write( "the difference is = 15.41993616 which is 15.42 pounds rounded to 2 decimal places.\r<BR>\n" );
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document.write( "you said 18 pounds.\r<BR>\n" );
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document.write( "i suspect you lost 2 marks because you rounded your numbers up front.\r<BR>\n" );
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document.write( "unless you are specifically asked to round your numbers in order to get a rough estimate, you need to use the exact values for the calculations and only round at the end.\r<BR>\n" );
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document.write( "your estimate versus the actual difference was about (18/15.42 - 1) * 100 = roughly 17% too high rounded to the nearest percent. </SPAN>\n" );
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