document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=421181>Question 421181</A>: <I><SPAN STYLE=\"word-break: break-all;\">  Please solve this question:<BR>\n" );
document.write( "The ratio of boys to girls in Mr.Peter class is 3:4. On the last exam, 3/4 of the boys passed the exam and 4/5 of the girls passed. If a students exam paper is chosen at random, what is the probability that it has a passing grade?\r<BR>\n" );
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document.write( " also\r<BR>\n" );
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document.write( "How to do it on TI-84\r<BR>\n" );
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document.write( "Thanks </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #294169 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=294169\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The ratio of boys to girls in Mr.Peter class is 3:4.<BR>\n" );
document.write( "# of boys = 3x<BR>\n" );
document.write( "# of girls = 4x<BR>\n" );
document.write( "Total # of boys and girls = 7x<BR>\n" );
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document.write( "On the last exam, 3/4 of the boys passed the exam and 4/5 of the girls passed.<BR>\n" );
document.write( "(3/4)(3x) = (9/4)x boys passed<BR>\n" );
document.write( "(4/5)(4x) = (16/5)x girls passed<BR>\n" );
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document.write( "If a students exam paper is chosen at random, what is the probability that it has a passing grade? <BR>\n" );
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document.write( "Total number who passed = [(9/4)+(16/5)]x = (45+56)/20 = (101/20)x<BR>\n" );
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document.write( "P(passed) = [101/20]x/7x = 101/140 = 0.7214<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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