document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1193357>Question 1193357</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The probability that Neil studies his lesson is 3/7. The probability that he will get good grades is 1/5. What is the probability that he will get good grades given that he will study his lessons? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #825384 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52800)</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=825384\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "The probability that Neil studies his lesson is 3/7. The probability that he will get good grades is 1/5. <BR>\n" );
document.write( "What is the probability that he will get good grades given that he will study his lessons?<BR>\n" );
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document.write( "Regarding this post, I think that the problem in the post is posed incorrectly.\r<BR>\n" );
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document.write( "To be posed correctly, the problem must provide explicitly the probability that \r<BR>\n" );
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document.write( "    \"Neil will get good grades if he will study his lessons.\"\r\n" );
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document.write( "In other words, the probability of the intersection of the two events must be given in the problem as a part of the input.\r<BR>\n" );
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document.write( "But it is missed in the post.\r<BR>\n" );
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document.write( "The assumption made by the other tutor that this probability is the difference of two other probabilities \r<BR>\n" );
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document.write( "has no any reasonable base.\r<BR>\n" );
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document.write( "So, my advise/instruction to the visitor is double check your input.\r<BR>\n" );
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document.write( "It is a standard problem on \"conditional probability\", <BR>\n" );
document.write( "but significant part of the problem's input is carelessly missed.\r<BR>\n" );
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document.write( "As worded, &nbsp;printed, &nbsp;posted and presented, &nbsp;this  &nbsp;\" problem \" &nbsp;is &nbsp;DEFECTIVE.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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