document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1141514>Question 1141514</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Need help with the following question. Please show work. Much appreciated, thank you!\r<BR>\n" );
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document.write( "It is known that 20% of drivers in Canada will drive after smoking marijuana. If 18 drivers are randomly selected, what is the probability that:\r<BR>\n" );
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document.write( "a) 4 or more will drive after smoking marijuana?\r<BR>\n" );
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document.write( "b) At least one will drive after smoking marijuana?\r<BR>\n" );
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document.write( "c)Less than 3 will drive after smoking marijuana? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #762107 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=762107\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use the binomial probability formula<BR>\n" );
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document.write( "Probability (P) (k successes out of n trials) = nCk * p^k * (1-p)^(n-k), p is the probability of success, nCk = n!/(k! * (n-k)!)<BR>\n" );
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document.write( "for this problem, p = 0.20, n=18<BR>\n" );
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document.write( "(a)  summation from i = 4 to 18 of P(i out of 18 trials) = 0.4999<BR>\n" );
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document.write( "(b)  1 - P(0 successes out of 18 trials) = 1 - 0.0180 = 0.9820<BR>\n" );
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document.write( "(c)  summation from i = 0 to 2 of P(i out of 18 trials) = 0.2713<BR>\n" );
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