document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1055034>Question 1055034</A>: <I><SPAN STYLE=\"word-break: break-all;\"> use a normal approximation to find the probability of the indicated scores, assume that n=100 and p=0.22\r<BR>\n" );
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document.write( "probability that x is at least 25\r<BR>\n" );
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document.write( "probability that x is exactly 19 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #670302 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=670302\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  use a normal approximation to find the probability of the indicated scores, assume that n=100 and p=0.22 <BR>\n" );
document.write( "probability that x is at least 25<BR>\n" );
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document.write( "mean = n*p = 22<BR>\n" );
document.write( "std = sqrt(22*0.78) = 4.14<BR>\n" );
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document.write( "P(x >= 25) ~ P(x >= 24.5)<BR>\n" );
document.write( "z(24.5) = (24.5-22)/4.14 = 0.60<BR>\n" );
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document.write( "p(x >= 25) = P(z >= 0.6) = normalcdf(0.6,100) = 0.2743<BR>\n" );
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document.write( "probability that x is exactly 19 <BR>\n" );
document.write( "P(x = 19) ~ P(18.5 <= x <= 19.5)<BR>\n" );
document.write( "z(18.5) = (18.5-22)/4.14 = -0.85<BR>\n" );
document.write( "z(19.5) = (19.5-22)/4.14 = 0.60<BR>\n" );
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document.write( "P(x = 19) ~ P(-0.85<= z <= 0.6) = normalcdf(-0.85,0.6) = 0.5281<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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