document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=870619>Question 870619</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Pens are sold in packets of 15 pens per packet. The pens are of different colour and 20% are red.<BR>\n" );
document.write( "a) Show that the probability of a randomly chosen packet of pens containing 3 or more red ones is 0.602.<BR>\n" );
document.write( "b) Jack buys 6 packets of pen. Find the probability that at least 5 of the packets contain 3 or more red pens.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #525035 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=525035\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> p (red) = .20,  n = 15<BR>\n" );
document.write( "a) P(x &#8805; 3) = 1 - binomcdf(15, .20, 2)= .602 <BR>\n" );
document.write( "0r<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P+%28x%29=+highlight_green%28nCx%29%28p%5Ex%29%28q%29%5E%28n-x%29+ ALIGN=MIDDLE  ALT=\"P+%28x%29=+highlight_green%28nCx%29%28p%5Ex%29%28q%29%5E%28n-x%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "1 - P(0) + P(x=1) + P(x=2) = 1 - (.035 + .132 + .231) = 1 - .398 = .602<BR>\n" );
document.write( "b) p (red) = .20, n = 6<BR>\n" );
document.write( "  P(x &#8804; 5) = 1 - p(x = 6) = 1 - (.2)^6 = 1 - .0001 = .9999<BR>\n" );
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