document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1150436>Question 1150436</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The customer accounts at a certain departmental store have an average balance of Shs.480 and a standard deviation of Shs.160. Assuming that the account balances are normally distributed  <BR>\n" );
document.write( "i)What proportion of the accounts is over Shs.600? 			(2 marks)<BR>\n" );
document.write( "ii)What proportion of the accounts is between Shs.400 and Shs.600	(2 marks)<BR>\n" );
document.write( "iii) What proportion of the accounts is between Shs.240 and Shs.360	(2 marks) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #772358 by </B><A HREF=/tutors/aboutme.mpl?userid=Glaviolette><B>Glaviolette(140)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Glaviolette><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=Glaviolette><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=772358\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i) z = (600-480)/160 = 0.75<BR>\n" );
document.write( "From z-table, P(>Shs.600) = 1 - 0.7734 = 0.2266<BR>\n" );
document.write( "ii) z = (400-480)/160 = -0.5<BR>\n" );
document.write( "Using previous answer and area for z = -0.5 (0.3085), P(Shs.400<x<Shs.600) = 0.7734 - 0.3085 = 0.4649<BR>\n" );
document.write( "iii) z = (240-480)/160 = -1.5<BR>\n" );
document.write( "z = (360-480)/160) = -0.75<BR>\n" );
document.write( "P(Shs.240<x<Shs.360) = 0.2266 - 0.0668 = .1598<BR>\n" );
document.write( "   </SPAN>\n" );
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