document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1195911>Question 1195911</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A film-processing company claims that the owners of digital cameras store on average more than fifteen<BR>\n" );
document.write( "pictures on their cameras, before the eventually download these to a computer or print. A random sample<BR>\n" );
document.write( "of 10 digital camera owners produced the data below on the number of pictures stored on their digital<BR>\n" );
document.write( "cameras.<BR>\n" );
document.write( "25 6 22 26 31 18 13 20 14 2\r<BR>\n" );
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document.write( "3.1) Test this claim at the 10 % level of significance. (10 marks)\r<BR>\n" );
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document.write( "3.2) Estimate with 95 % confidence the mean number of pictures stored on digital cameras.\r<BR>\n" );
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document.write( "(5 marks) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #828549 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=828549\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ho: mean is 15<BR>\n" );
document.write( "Ha: mean is not 15<BR>\n" );
document.write( "alpha=0.10 p{reject Ho|Ho true}<BR>\n" );
document.write( "test statistic is a t (0.95; df=9) critical value is |t| >1.833<BR>\n" );
document.write( "mean is 17.7 and s=9.08<BR>\n" );
document.write( "t=(17.7-15)/9.08/sqrt(10)<BR>\n" );
document.write( "=0.94<BR>\n" );
document.write( "fail to reject the Ho; insufficient evidence to say that there is a difference at the 10% level. p-value=0.37<BR>\n" );
document.write( "confidence interval will contain 15; it is 17.7+/-2.262*9.08/sqrt(10); the latter=6.50<BR>\n" );
document.write( "The 95% confidence interval is 17.7+/- 6.50 or (11.20, 24.20) units pictures. </SPAN>\n" );
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