document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=555507>Question 555507</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A new computer virus can enter the system through the e-mail or through the internet. There is 30% chance of receiving this virus through the e-mail. There is a 40% chance of receiving it through the internet. In addition, the virus enters the system simultaneously through e-mail and the internet with probability 0.15. What is the probability that the virus does not enter the system at all? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #361821 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=361821\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A venn diagram will help understand this.<BR>\n" );
document.write( ".15 both e-mail and internet<BR>\n" );
document.write( ".15 e-mail only<BR>\n" );
document.write( ".25 internet only<BR>\n" );
document.write( "----add<BR>\n" );
document.write( ".55 total<BR>\n" );
document.write( ".<BR>\n" );
document.write( "1-.55=.45 the probability that the virus does not enter the system at all.<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Ed </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );