document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1131185>Question 1131185</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Mrs. DiNardo's physics class has 115 students, classified by academic year and gender, as illustrated in<BR>\n" );
document.write( "the following table. Mrs. DiNardo randomly chooses one student to collect yesterday's work. What is the<BR>\n" );
document.write( "probability that she selects a female, given that she chooses randomly from only the juniors? Express<BR>\n" );
document.write( "your answer as a fraction in lowest terms or a decimal rounded to the nearest millionth.\r<BR>\n" );
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document.write( "Mrs. DiNardo's Physics Class<BR>\n" );
document.write( "Classification Males Females<BR>\n" );
document.write( "Freshmen        20 Males    9 Females<BR>\n" );
document.write( "Sophomores      18 Males    15 Females<BR>\n" );
document.write( "Juniors         10 Males    12 Females <BR>\n" );
document.write( "Seniors         12 Males    19 Females </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #747814 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13198)</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=747814\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "\"...given that she chooses randomly from only the juniors...\" means she is only choosing from among the 22 juniors.  12 of the 22 juniors are female, so the probability is 12/22 = 6/11.<br><BR>\n" );
document.write( "Formally (the way conditional probability is usually taught),<br><PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "                        P(junior AND female)   12/115   12    6\r\n" );
document.write( "     P(female|junior) = -------------------- = ------ = -- = --\r\n" );
document.write( "                            P(junior)          22/115   22   11\r\n" );
document.write( "</PRE><br> </SPAN>\n" );
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