document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1116434>Question 1116434</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A class of 18 students are taking an exam. The<BR>\n" );
document.write( "probability of passing an exam is higher than the<BR>\n" );
document.write( "probability of failing. If the probability that half the<BR>\n" );
document.write( "students pass the exam is 0.0642543198, find the<BR>\n" );
document.write( "probability of passing the exam. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #731372 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=731372\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The probability that 9 of 18 students pass, if the probability of passing is p and the probability of failing is (1-p), is<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C%2818%2C9%29p%5E9%281-p%29%5E9 ALIGN=MIDDLE  ALT=\"C%2818%2C9%29p%5E9%281-p%29%5E9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "So we have<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C%2818%2C9%29p%5E9%281-p%29%5E9+=+.0642543198 ALIGN=MIDDLE  ALT=\"C%2818%2C9%29p%5E9%281-p%29%5E9+=+.0642543198\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p%5E9%281-p%29%5E9+=+1.321561493%2A10%5E-6 ALIGN=MIDDLE  ALT=\"p%5E9%281-p%29%5E9+=+1.321561493%2A10%5E-6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p%281-p%29+=+%281.321561493%2A10%5E-6%29%5E%281%2F9%29+=+2%2F9 ALIGN=MIDDLE  ALT=\"p%281-p%29+=+%281.321561493%2A10%5E-6%29%5E%281%2F9%29+=+2%2F9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "This is more easily solved by inspection than by formal algebra: p = 2/3, 1-p = 1/3.<br><BR>\n" );
document.write( "Answer: The probability of passing the exam is 2/3. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );