document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=204227>Question 204227</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/1405802111/algebrahomeworkh>Longman Mathematics for IGCSE </A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Lauren is shooting at a target at afair. If she hits the target she recieves 50 pences,but if she misses she has to pay 20 pences for the shot. After 15 shots, Lauren finds she has made a profit of 1.20 pounds. How many hits has she had?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #154189 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=154189\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">     Lauren is shooting at a target at afair. If she hits the target she recieves 50 pences,but if she misses she has to pay 20 pences for the shot. After 15 shots, Lauren finds she has made a profit of 1.20 pounds. How many hits has she had? <BR>\n" );
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document.write( "Let h = number of hits<BR>\n" );
document.write( "and m = number of misses<BR>\n" );
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document.write( "Since we have two unknowns, we'll need two equations.<BR>\n" );
document.write( "Equation 1 is derived from the fact she took 15 shots:<BR>\n" );
document.write( "h + m = 15<BR>\n" );
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document.write( "Equation 2 is derived from the profit of 1.20<BR>\n" );
document.write( "(100 pences is equivalent to 1 pound)<BR>\n" );
document.write( "(50/100)h - (20/100)m = 1.20<BR>\n" );
document.write( "50h - 20m = 120<BR>\n" );
document.write( "5h - 2m = 12<BR>\n" );
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document.write( "Using the \"substitution method\", we solve equation 1 for m:<BR>\n" );
document.write( "h + m = 15<BR>\n" );
document.write( "m = 15-h<BR>\n" );
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document.write( "We substitute the above into equation 2 and solve for h:<BR>\n" );
document.write( "5h - 2m = 12<BR>\n" );
document.write( "5h - 2(15-h) = 12<BR>\n" );
document.write( "5h - (30-2h) = 12<BR>\n" );
document.write( "5h - 30 + 2h = 12<BR>\n" );
document.write( "7h - 30 = 12<BR>\n" );
document.write( "7h = 42<BR>\n" );
document.write( "h = 6 <BR>\n" );
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document.write( "Solution: 6 hits<BR>\n" );
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