document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1170807>Question 1170807</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The salaries of the employees in a company follow the normal distribution with mean $16000 and standard deviation $800.\r<BR>\n" );
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document.write( "(a)     What is the probability that the salary of an employee is higher than $18000?   \r<BR>\n" );
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document.write( "(b)     There is 80% chance that the salary of an employee is less than $t. Find the value of t.                                                                                                   \r<BR>\n" );
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document.write( "(c)     If 20 employees are randomly chosen from the company and the mean salary of the employees is calculated. The manager of the company claims that over 20% of the mean salaries of the employee are higher than $16200. Do you agree? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #795685 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=795685\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> z=(x-mean)/sd<BR>\n" );
document.write( "z > (18000-16000)/800 or 2.5<BR>\n" );
document.write( "that probability is 0.0062<BR>\n" );
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document.write( "z (0.80)=0.8416<BR>\n" );
document.write( "0.8416=(t-16000)/800<BR>\n" );
document.write( "673.29=t-16000, will round to nearest integer<BR>\n" );
document.write( "t=$16,673.<BR>\n" );
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document.write( "z=(16200-16000)/800/sqrt(20)<BR>\n" );
document.write( "-200*sqrt(20)/800=.<BR>\n" );
document.write( "=1.118<BR>\n" );
document.write( "That probability of z> than that value is 13.2%<BR>\n" );
document.write( "The sd of the sampling distribution with n=20 has mean $16000 as before, but sd is 178.88 </SPAN>\n" );
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