document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=494106>Question 494106</A>: <I><SPAN STYLE=\"word-break: break-all;\"> It is found that 20% of the students failed an IELTS test. suppose 25 students are randomly selected from the total pool. Answer the following question<BR>\n" );
document.write( "a) what is the probability that exactly 4 students failed the test?<BR>\n" );
document.write( "b) what is the probability that more than 4 students failed the test? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #335533 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=335533\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> It is found that 20% of the students failed an IELTS test. suppose 25 students are randomly selected from the total pool. Answer the following question<BR>\n" );
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document.write( "Binomial Problem with n = 25 and p = 0.20<BR>\n" );
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document.write( "a) what is the probability that exactly 4 students failed the test?<BR>\n" );
document.write( "P(x=4) = 25C4(0.2)^4*(0.8)^21 = 0.1867<BR>\n" );
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document.write( "b) what is the probability that more than 4 students failed the test?<BR>\n" );
document.write( "P(5<= x <= 25) = 1 - P(0<= x <=4) = 1-0.4207 = 0.5793<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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