document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1124794>Question 1124794</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose that 50 identical batteries are being tested. After 8 hours of continuous use, assume that a given battery is still operating with a probability of 0.70 and has failed with a probability of 0.30. \r<BR>\n" );
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document.write( "What is the probability that fewer than 25 batteries will last at least 8 hours? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #741103 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=741103\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The mean would be 35 batteries (50*0.7)<BR>\n" );
document.write( "The variance would be 10.5 (mean*0.3)<BR>\n" );
document.write( "The sd would be sqrt (10.5) or 3.24<BR>\n" );
document.write( "the continuity correction factor would be z<(24.5-35)/3.24 of z< 10.5/3.24 =3.24<BR>\n" );
document.write( "probability is 0.0006\r<BR>\n" );
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document.write( "Check 50C24*0.7^24*0.3^26=0.000592<BR>\n" );
document.write( "50C23*0.7^24*0.3^27=0.00016<BR>\n" );
document.write( "the others will be far smaller. </SPAN>\n" );
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