document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1022861>Question 1022861</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose a certain traffic light shows a red light for 42 seconds, a green light for 45 seconds, and a yellow light for 5 seconds. \r<BR>\n" );
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document.write( "If you look at this light at a randomly chosen instant, what is the probability that you see a red or yellow light? (Enter your probability as a fraction.) <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 #638463 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=638463\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> By the addition law, P(R or Y) = P(R) + P(Y) - P(R and Y).  <BR>\n" );
document.write( "But R and Y are mutually exclusive events, so P(R and Y) = 0.\r<BR>\n" );
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document.write( "==>  P(R or Y) = P(R) + P(Y)  = 42/92 + 5/92 = 47/92. </SPAN>\n" );
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