document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=695227>Question 695227</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A survey done for a magazine found that 77% of bike riders sometimes ride without a helmet. If four bike riders are randomly selected, find the probability that at least one of the riders does not wear a helmet at all times. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #428377 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=428377\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A survey done for a magazine found that 77% of bike riders sometimes ride without a helmet. If four bike riders are randomly selected, find the probability that at least one of the riders does not wear a helmet at all times.<BR>\n" );
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document.write( "Binomial Problem with n = 4 and p(helmet) = 0.77 ; p(no helmet) = 0.23<BR>\n" );
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document.write( "P(x >=1 no helmet) = 1 - P(all wear helmets) = 1- 0.77^4 = 0.6485<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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