document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=572725>Question 572725</A>: <I><SPAN STYLE=\"word-break: break-all;\"> This is from a practice assignment and I cannot figure out how to solve the question.  I would appreciate an explanation as to how the answer is obtained rather than just the answer.\r<BR>\n" );
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document.write( "A math professor notices that scores from a recent exam are normally distributed with a mean of 64 and a standard deviation of 5. Answer the following questions using integer values.  What score do 75% of the students exam scores fall below?\r<BR>\n" );
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document.write( "And, the professor decides to grade on a curve.  If he wants .15% of the students to get an A, what is the minimum score required.\r<BR>\n" );
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document.write( "I have tried a \"calculator\" I found online and the answers it provided gave me 50% credit and I don't know which answer is correct as I don't know how to do the actual calculation.  First answer - 67.3587.  Second answer - 58.8284.\r<BR>\n" );
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document.write( "I would appreciate referral to any valid resources as it has been many, many years since I took a math class.\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 #368568 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=368568\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A math professor notices that scores from a recent exam are normally distributed with a mean of 64 and a standard deviation of 5. Answer the following questions using integer values. What score do 75% of the students exam scores fall below? <BR>\n" );
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document.write( "Find the z-value with a left tail of 75%.<BR>\n" );
document.write( "Using a TI-84 I get invNorm(0.75) = 0.6745<BR>\n" );
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document.write( "Using x = zs+u solve for \"x\"<BR>\n" );
document.write( "x = 0.6745*5+64 = 67 when rounded down<BR>\n" );
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document.write( "And, the professor decides to grade on a curve. If he wants 15% <BR>\n" );
document.write( "of the students to get an A, what is the minimum score required.<BR>\n" );
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document.write( "Find the z-value with a left tail of 0.85<BR>\n" );
document.write( "invNorm(0.85) = 1.0364<BR>\n" );
document.write( "x = 1.0364*5+64 = 69 when rounded down<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( " </SPAN>\n" );
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