document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1160868>Question 1160868</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a mathematics professor gives an \"extra-credit\" (bonus marks) problem on a test. if it is done correctly, 15 points are added to the test score, and if it is done partially correctly, 5 points are added; otherwise 5 points are subtracted. suppose a student's probability of getting the problem completely right is 1/4, and only partially correct is 1/2. find the student's mathematical expectation E (expected value) for extra credit. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #784273 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52781)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=784273\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
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document.write( "    E = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F4%29%2A15 ALIGN=MIDDLE  ALT=\"%281%2F4%29%2A15\"   DISABLED_style= \"max-width:90%; height:auto;\" > + <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29%2A5 ALIGN=MIDDLE  ALT=\"%281%2F2%29%2A5\"   DISABLED_style= \"max-width:90%; height:auto;\" > - <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F4%29%2A5 ALIGN=MIDDLE  ALT=\"%281%2F4%29%2A5\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2815+%2B+10+-+5%29%2F4 ALIGN=MIDDLE  ALT=\"%2815+%2B+10+-+5%29%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20%2F4 ALIGN=MIDDLE  ALT=\"20%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 5 bonus marks.    <U>ANSWER</U>\r\n" );
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document.write( "Solved.\r<BR>\n" );
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