document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=321276>Question 321276</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The mean price of computers at an electronics store is $850, with a standard deviation of $90. A random sample of 21 televisions is drawn from this population. What is the probability that the mean price of the sample is less than $830?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #230119 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=230119\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  The mean price of computers at an electronics store is $850, with a standard deviation of $90. <BR>\n" );
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document.write( "A random sample of 21 televisions is drawn from this population. What is the probability that the mean price of the sample is less than $830? <BR>\n" );
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document.write( "mean of the distribution of sample means = 850<BR>\n" );
document.write( "std of the distribution of sample means = 90/sqrt(21)<BR>\n" );
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document.write( "t(830) = (830-850)/[0.90/sqrt(21)] = -1.0184<BR>\n" );
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document.write( "P(x< 830) = P(t< -1.0184 when df=20) = 0.1603<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. <BR>\n" );
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