document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1142643>Question 1142643</A>: <I><SPAN STYLE=\"word-break: break-all;\"> An experienced teacher writes an exam so that, on average, about 5% of students will earn an A grade. If she has 50 students in her class and their performance is independent, what is the probability that at least one student gets an A? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #763359 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52906)</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=763359\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "An experienced teacher writes an exam so that, on average, about 5% of students will earn an A grade. <BR>\n" );
document.write( "If she has 50 students in her class and their performance is independent, what is the probability that at least one student gets an A?<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;I am writing my post with the only one goal: to explain (and to make it clear the fact) that Edwin solved, actually, \r<BR>\n" );
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document.write( "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<U>different problem</U> than is written in the post.\r<BR>\n" );
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document.write( "The problem solved by Edwin is <U>THIS</U>:\r<BR>\n" );
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document.write( "    The class contains 50 students. On exam, the probability that every single student will earn an A grade is 5%.\r\n" );
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document.write( "    What is the probability that at least one student gets an A ?\r\n" );
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document.write( "My formulation is &nbsp;CRYSTALLY &nbsp;clear, &nbsp;and it is an example &nbsp;(A STANDARD, &nbsp;actually) &nbsp;on how such problems &nbsp;MUST &nbsp;BE &nbsp;FORMULATED.\r<BR>\n" );
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document.write( "The original formulation in the post is very blurred,\r<BR>\n" );
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document.write( "and I do not think that it can, in general, be solved as it is formulated.\r<BR>\n" );
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document.write( "Edwin made it absolutely correct, &nbsp;when he changed the original formulation;\r<BR>\n" );
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document.write( "but he did it without acknowledgment, &nbsp;which, &nbsp;in my view, &nbsp;is not right.\r<BR>\n" );
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document.write( "I hope &nbsp;(and I am almost sure) &nbsp;that Edwin understands it well,\r<BR>\n" );
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document.write( "but I am writing these words for the future generations of students who will read this post &nbsp;(if they do . . . ).\r<BR>\n" );
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document.write( "As it was formulated in the post originally, &nbsp;is totally different problem.\r<BR>\n" );
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document.write( "At this forum, &nbsp;I am observing last days &nbsp;<U>A &nbsp;FLOW</U>&nbsp; of problems &nbsp;VERY&nbsp; poorly and badly formulated.\r<BR>\n" );
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document.write( "My impression is that they are / were created by person having zero knowledge on &nbsp;<U>WHAT &nbsp;IS &nbsp;a &nbsp;Math &nbsp;problem</U> \r<BR>\n" );
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document.write( "and how it should be formulated.\r<BR>\n" );
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document.write( "My hypothesis is that some former English teacher on the phone, &nbsp;without an experience in Math, <BR>\n" );
document.write( "receives formulation from the outside and dispatches them to the forum and back, making small business . . . \r<BR>\n" );
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document.write( "It is the only way on how I can explain this flow of false Math problems arriving to the forum.\r<BR>\n" );
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document.write( "If it is so, &nbsp;then &nbsp;<U>I &nbsp;INSISTENTLY &nbsp;recommend</U> to the managers of this project to &nbsp;<U>REPLACE &nbsp;this person &nbsp;URGENTLY</U>, \r<BR>\n" );
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document.write( "since he &nbsp;(or she) &nbsp;is not able to perform his &nbsp;(or her) &nbsp;functions properly.\r<BR>\n" );
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