document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=922357>Question 922357</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The lifetimes of a certain brand of high intensity batteries are known to be normally distributed with a mean of 2,400 hours and a standard deviation of 300 hours.  A random sample of 64 of these light bulbs is taken. The probability is 0.15 that the sample mean lifetime is more than how many hours?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #559504 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=559504\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> mean of 2,400 hours and a standard deviation of 300 hours<BR>\n" );
document.write( "z = invNorm(.85) = 1.0364<BR>\n" );
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document.write( "1.0364 (300/sqrt(64)) + 2400 = xbar\r<BR>\n" );
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