document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1104729>Question 1104729</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A recent news report had found that 68% of all internet searches use Google (a<BR>\n" );
document.write( "website used for search). Suppose a random sample of 50 searches is taken from a database that contains<BR>\n" );
document.write( "records of internet activity and searches.<BR>\n" );
document.write( "29. What is the probability that exactly 25 searches are conducted on Google?<BR>\n" );
document.write( "30. What is the probability that at least 40 searches are conducted on Google?<BR>\n" );
document.write( "31. How likely is it that less than 30 searches are conducted on Google?<BR>\n" );
document.write( "32. On average how many searches out of 50 should we expect to be conducted on Google? With what<BR>\n" );
document.write( "standard deviation?<BR>\n" );
document.write( "33. Would it be unusual for 45 of the searches to be conducted using Google? Explain.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #720505 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=720505\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 29. 50C250.68^25*0.32^25=0.0035<BR>\n" );
document.write( "30. Mean is np=34; variance is np(1-p)=34*0.32=10.68; sd=sqrt (var)=3.27. This answers 32.<BR>\n" );
document.write( "using continuity correction factor z>(39.5-34)/3.27=1.68.  Probability is 0.0465<BR>\n" );
document.write( "31. Fewer than 30 is (29.5-34)/3.27 or z<-1.38, probability is 0.0838.<BR>\n" );
document.write( "33. For 45, the probability is 50C450.68^45*0.32*5=0.0002. Unusual. The mean is 34 and the sd is 3.27. Most of the probability will involve searches between 31 and 37.\r<BR>\n" );
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