document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=455595>Question 455595</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A chain of pharmacies has collected data on customer waiting times for filling prescriptions. They've found that 10% of the time customers are waiting longer than 15 minutes. In order to improve customer satisfaction, the company has stated a goal fo having no more than 2% of their customers wait longer than 15 minutes. If we assume the distribution is normal and the standard deviation (sigma) is 3 minutes, waht should the mean of the waiting times be equal to?\r<BR>\n" );
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document.write( "I tried to calculate based on the z score of .98 cumulative area and the equation z= x-m/o (m being mean and o being std. dev.)Using the empirical rule, I know the answer I am getting can not be correct. Any suggestions? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #312863 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=312863\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The z score for an alpha of .02 is 2.0537<BR>\n" );
document.write( "z=(x-m)/s<BR>\n" );
document.write( "(15-m)/3=2.0537<BR>\n" );
document.write( "15-m=6.1611<BR>\n" );
document.write( "-m=-8.8389<BR>\n" );
document.write( "m=8.8389<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Ed </SPAN>\n" );
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