document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=917014>Question 917014</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose the battery life on an apple iPhone is approximately normally distributed with a mean of 7 hours and a standard deviation of 0.6 hours. Find the following:\r<BR>\n" );
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document.write( "1)What is the probability that a fully charged phone will last somewhere between 4 and 5.9 hours? \r<BR>\n" );
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document.write( "2) what battery life time would seperate  the bottom 30% from the rest of the life times?\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 #556456 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=556456\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Population: mean = 7hr, SD = .6hrs,  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z+=blue+%28x+-+mu%29%2Fblue%28sigma%29 ALIGN=MIDDLE  ALT=\"z+=blue+%28x+-+mu%29%2Fblue%28sigma%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "1) P(4 < x< 9) = P(-3/.6 < z <  2/.6) = normalcdf(-5, 3.3333)  0r .99957 - .00003 = .99954 </SPAN>\n" );
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