document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=600420>Question 600420</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The monthly utility bills are normally distributed with a mean value of $160 and a standard deviation of $25.<BR>\n" );
document.write( "(a) Find the probability of having a utility bill between 120 and 180.<BR>\n" );
document.write( "(b) Find the probability of having a utility bill less than $120.<BR>\n" );
document.write( "(c) Find the probability of having a utility bill more than $210.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #379326 by </B><A HREF=/tutors/aboutme.mpl?userid=sniper619><B>sniper619(1)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sniper619><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=379326\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a) P(120< x <180) = P( (120-160/25)< z < (180-160/25) )<BR>\n" );
document.write( "                  = P( -1.6 < z < 0.8)<BR>\n" );
document.write( "                  = P(z < 0.8) - P(z > 1.6)<BR>\n" );
document.write( "                  = 0.7881 - (1-0.9452)<BR>\n" );
document.write( "                  = 0.7881 - 0.0548<BR>\n" );
document.write( "                  = 0.7333\r<BR>\n" );
document.write( "\n" );
document.write( "b) P( x<120 ) = P( z < (120-160/25) ) <BR>\n" );
document.write( "              = P( z < -1.6 )<BR>\n" );
document.write( "              = 1 - 0.9452<BR>\n" );
document.write( "              = 0.0548\r<BR>\n" );
document.write( "\n" );
document.write( "c) P( x>210 ) = P( z > (210-160/25) )<BR>\n" );
document.write( "              = P( z > 2 )<BR>\n" );
document.write( "              = 1 - 0.9772<BR>\n" );
document.write( "              = 0.0228\r<BR>\n" );
document.write( "\n" );
document.write( "Note: Used a Normal Distribution Function Table. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );