document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1181977>Question 1181977</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average amount of time a person exercises daily is 22.7 minutes in a population. A random sample of 20 people showed an average of 29.8 minutes in time with a standard deviation of 9.8 minute. At a = 0.01, can it be concluded that the average differs from the population average? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #811939 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=811939\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ho: mean is 22.7 min<BR>\n" );
document.write( "Ha: mean is not 22.7 min<BR>\n" );
document.write( "alpha=0.01 p{reject Ho|Ho true}<BR>\n" );
document.write( "test is a t(0.995, df=19)<BR>\n" );
document.write( "critical value |t| >2.861<BR>\n" );
document.write( "calculation is t=(29.8-22.7)/9.8/sqrt(20). basically difference in means divided by the standard error.<BR>\n" );
document.write( "=7.1*sqrt(20)/9.8<BR>\n" );
document.write( "=3.24<BR>\n" );
document.write( "Reject the null hypothesis and conclude that the true value is more than 22.7 minutes<BR>\n" );
document.write( "p-value=0.0086 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );