document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=232448>Question 232448</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a school bus contains 8 first graders and 10 second graders. if two children are are what is the probability that at least one is a second grader.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #171776 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=171776\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a school bus contains 8 first graders and 10 second graders. if two children are are what is the probability that at least one is a second grader.<BR>\n" );
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document.write( "P(selecting a second grader) = 10/18 = 5/9<BR>\n" );
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document.write( "Your Problem:<BR>\n" );
document.write( "P(at least one) + P(none) = 1<BR>\n" );
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document.write( "P(at least one second grader among 2 selected) <BR>\n" );
document.write( "= 1 - P(no second grader amoung two selected)<BR>\n" );
document.write( "= 1 - 2C0(5/9)^0(4/9)^2 = 1- (4/9)^2 = 1-16/81 = 65/81<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.  </SPAN>\n" );
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