document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=341087>Question 341087</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Demand for residential electricity at 6:00 P.M. on the first Monday in October in Santa Theresa County is normally distributed with a mean of 4,905 MW (megawatts) and a standard deviation of 355 MW. Due to scheduled maintenance and unexpected system failures in a generating station the utility can supply a maximum of 5,200 MW at that time. What is the probability that the utility<BR>\n" );
document.write( "will have to purchase electricity from other utilities or allow brownouts?\r<BR>\n" );
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document.write( "So I have tried this: \r<BR>\n" );
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document.write( "(5200-4905)/355 = 0.830986\r<BR>\n" );
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document.write( "I do not know if I have answered this question correctly. Please review and help me, if you can.\r<BR>\n" );
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document.write( "Thank you!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #244229 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=244229\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Demand for residential electricity at 6:00 P.M. on the first Monday in October in Santa Theresa County is normally distributed with a mean of 4,905 MW (megawatts) and a standard deviation of 355 MW. <BR>\n" );
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document.write( "Due to scheduled maintenance and unexpected system failures in a generating station the utility can supply a maximum of 5,200 MW at that time. <BR>\n" );
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document.write( "What is the probability that the utility will have to purchase electricity from other utilities or allow brownouts? <BR>\n" );
document.write( "So I have tried this: <BR>\n" );
document.write( "z(5200) = (5200-4905)/355 = 0.8310<BR>\n" );
document.write( "Note: You have found the z-value associated with 5200.<BR>\n" );
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document.write( "You now need to find the probability that z is greater than 0.8310<BR>\n" );
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document.write( "P(x > 5200) = P(z > 0.8310) = normalcdf(0.8310,100) = 0.2030<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. <BR>\n" );
document.write( " </SPAN>\n" );
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