document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=123207>Question 123207</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Frank got scores of 75, 83, and 79 on his first three tests. What score does he need to make on his next test to have an average of 80? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #90518 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=90518\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When Frank completes his next test, he will have done 4 tests. If he is to average 80 on these <BR>\n" );
document.write( "4 tests, he will need to score a total of 320 points on the 4 tests ... because 320 total<BR>\n" );
document.write( "points divided by 4 will result in an average of 80.<BR>\n" );
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document.write( "On the 3 tests he has completed already, Frank has scored 75 + 83 + 79 = 237 points. His<BR>\n" );
document.write( "next test has to add enough points to take the total to 320 points. So, on his next test<BR>\n" );
document.write( "Frank has to score 320 minus 237 points, and that means he must get 83 points on his next test.<BR>\n" );
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document.write( "Another tricky way to work this problem is to look at his present scores as they compare to<BR>\n" );
document.write( "the 80 average he wants after his next test. On his first test he got a 75. That is 5 points<BR>\n" );
document.write( "below his desired average. On his second test he got and 83 and that is 3 points above his<BR>\n" );
document.write( "desired average. On his third test he got 79 and this is 1 point below his desired average. <BR>\n" );
document.write( "That means relative to his desired average of 80 he is a total of 3 points below what he needs.<BR>\n" );
document.write( "This comes from -5 +3 -1 = -3 where the minus signs indicate the number of points below<BR>\n" );
document.write( "the desired average and the + sign indicates more than the desired average. Since after 3 <BR>\n" );
document.write( "tests he is 3 points below the desired average, on the next test he must score 3 points more than<BR>\n" );
document.write( "the desired average to counteract the shortfall. Therefore, he must score 83 points. This <BR>\n" );
document.write( "means that relative to the desired average of 80 on the 4 tests on each of the 4 tests he will<BR>\n" );
document.write( "have scored -5 +3 -1 +3 = 0, so he will be exactly on the 80 average (80 + 0). <BR>\n" );
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document.write( "Hope both methods make sense to you and help you to understand the problem a little better. <BR>\n" );
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