document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=250503>Question 250503</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a student has grades on three examinations of 70,86,and 78. what must the student earn on a fourth examination in order to have an average of at least 80? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #182387 by </B><A HREF=/tutors/aboutme.mpl?userid=actuary><B>actuary(112)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=actuary><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=182387\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Since the definition of \"average\" is ave = sum of all scores divided by the number of scores, we have 80 =(70+86+78+fourth exaximation score)/4\r<BR>\n" );
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document.write( "So 320 = 234 + fourth examination score (multiply both sides of the equation by 4 and add the known scores)\r<BR>\n" );
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document.write( "So 320-234 = fourth examination score (subtract 234 from each side of the equation\r<BR>\n" );
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document.write( "so fourth examination must be greater than or equal to 86 in order to have an average of at 80. </SPAN>\n" );
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