document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=274633>Question 274633</A>: <I><SPAN STYLE=\"word-break: break-all;\">  among com[anies doing highway or brige construction , 80% test employees for substance abuse . A study oinvolves the randam selection of 10 such companies. FIND the probability that exactly 5 of the 10 companies test for substance abuse.(b) find the probability at least half of the companies test for substance abuse.(c) For such groups of 10 companies , find the mean and standard for the number(among) that test for substance abuse. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #200400 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=200400\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> among companies doing highway or brige construction , 80% test employees for substance abuse. <BR>\n" );
document.write( "A study involves the random selection of 10 such companies. \r<BR>\n" );
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document.write( "a)FIND the probability that exactly 5 of the 10 companies test for substance abuse<BR>\n" );
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document.write( "P(x = 5) = 10C5(0.8)^5*(0.2)^5 = binompdf(10,0.8,5) = 0.0264<BR>\n" );
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document.write( "(b) Find the probability at least half of the companies test for substance abuse.<BR>\n" );
document.write( "P(5<= x <=10) = 1 - binomcdf(10,0.8,4) = 0.9936\r<BR>\n" );
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document.write( "c) For such groups of 10 companies , find the mean and standard deviation for the number(among 10) that test for substance abuse.<BR>\n" );
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document.write( "mean = np = 10*0.8 = 8<BR>\n" );
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document.write( "std = sqrt(npq) = sqrt(8*0.2) = sqrt(1.6) = 1.2649<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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