document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=868940>Question 868940</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If a hedgehog crosses a certain road before 7.00 a.m., the probability of being run over is 1/10. After 7.00a.m., the corresponding probability is 3/4. The probability of the hedgehog waking up early enough to cross before 7.00 a.m., is 4/5. What is the probability of the following events:<BR>\n" );
document.write( "(a) the hedgehog waking up too late to reach the road before 7.00 a.m.<BR>\n" );
document.write( "(b) the hedgehog waking up early and crossing the road in safety<BR>\n" );
document.write( "(c) the hedgehog waking up late and crossing the road in safety<BR>\n" );
document.write( "(d) the hedgehog waking up early and being run over<BR>\n" );
document.write( "(e) the hedgehog crossing the road in safety.<BR>\n" );
document.write( "PLEASE HELP! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #523952 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=523952\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Note that a - d are mutually inclusive events and e is mutually exclusive events<BR>\n" );
document.write( "a) 1 - 4/5 = 1/5 probability of waking up too late to reach the road before 7.00 a.m.<BR>\n" );
document.write( "b) 4/5 * (1 - 1/10) = 36/50 = 18/25 probability of waking up early and crossing the road in safety<BR>\n" );
document.write( "c) (1 - 4/5) * (1 - 3/4) = 1/20 probability of waking up late and crossing the road in safety <BR>\n" );
document.write( "d) probability of waking up early and being run over = 4/5 * 1/10 = 4/50 = 2/25<BR>\n" );
document.write( "e) probability of crossing the road in safety = 18/25 + 1/20 = 72/100 + 5/100 = 77/100\r<BR>\n" );
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