document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=914487>Question 914487</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 5.	The air pressure in a randomly selected tire put on a certain model new car is normally distributed with a mean value 31 psi and standard deviation 1 psi. \r<BR>\n" );
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document.write( "a)	What is the probability that the pressure for a randomly selected tire is between 30 psi and 32 psi?\r<BR>\n" );
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document.write( "b)	What is the maximum tire pressure for the bottom 25% of the cars?\r<BR>\n" );
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document.write( "c)	What is the median tire pressure of all cars of this model?\r<BR>\n" );
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document.write( "d)	If a sample of 25 tires is selected, what is the probability that the average air pressure of these tires is more than 31.5 psi?<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 #555159 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=555159\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> normally distributed with a mean value 31 psi and standard deviation 1 psi. <BR>\n" );
document.write( "a) What is the probability that the pressure for a randomly selected tire is between 30 psi and 32 psi? <BR>\n" );
document.write( "Empirical Rule(1SD from mean) 68%<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing%28400%2C200%2C-5%2C5%2C-.5%2C1.5%2C+graph%28400%2C200%2C-5%2C5%2C-.5%2C1.5%2C+exp%28-x%5E2%2F2%29%29%2C+green%28line%281%2C0%2C1%2Cexp%28-1%5E2%2F2%29%29%2Cline%28-1%2C0%2C-1%2Cexp%28-1%5E2%2F2%29%29%29%2Cgreen%28line%282%2C0%2C2%2Cexp%28-2%5E2%2F2%29%29%2Cline%28-2%2C0%2C-2%2Cexp%28-2%5E2%2F2%29%29%29%2Cgreen%28line%283%2C0%2C3%2Cexp%28-3%5E2%2F2%29%29%2Cline%28-3%2C0%2C-3%2Cexp%28-3%5E2%2F2%29%29%29%2Cgreen%28line%28+0%2C0%2C+0%2Cexp%280%5E2%2F2%29%29%29%2Clocate%284.8%2C-.01%2Cz%29%2Clocate%284.8%2C.2%2Cz%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "one  standard deviation from the mean accounts for about 68% of the set <BR>\n" );
document.write( "two standard deviations from the mean account for about 95%<BR>\n" );
document.write( "and three standard deviations from the mean account for about 99.7%.<BR>\n" );
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document.write( "0r P = normalcdf(30,32,31,1) <BR>\n" );
document.write( "0r  <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;\" > P = normalcdf(-1,1)<BR>\n" );
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document.write( " b) What is the maximum tire pressure X for the bottom 25% of the cars? <BR>\n" );
document.write( "1(invNorm(.25) + 31 = X<BR>\n" );
document.write( ".................<BR>\n" );
document.write( " c) What is the median tire pressure of all cars of this model? <BR>\n" );
document.write( "Normal Distribution(Mean Median & Mode the same):   31 psi<BR>\n" );
document.write( ".............<BR>\n" );
document.write( " d) If a sample of 25 tires is selected, what is the probability that the average air pressure of these tires is more than 31.5 psi?<BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z+=blue+%28x+-+mu%29%2Fblue%28sigma%2Fsqrt%28n%29%29+=+.5%2F%281%2F5%29 ALIGN=MIDDLE  ALT=\"z+=blue+%28x+-+mu%29%2Fblue%28sigma%2Fsqrt%28n%29%29+=+.5%2F%281%2F5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 2.5, <BR>\n" );
document.write( "P(x > 31.5) = normalcdf(2.5,100) </SPAN>\n" );
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