document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1162127>Question 1162127</A>: <I><SPAN STYLE=\"word-break: break-all;\"> ) Raw material used in the production of synthetic  fiber  is stored in a place which has no humidity control. Measurements of the relative  humidity  in  the  storage place and the moisture content of a sample of the raw material (both in percentages) on 12 days yielded the following results:	(10)\r<BR>\n" );
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document.write( "Humidity x	42	C5	50	4C	48	62	C1	C6	44	C9	55	48<BR>\n" );
document.write( "Moixture content y	<BR>\n" );
document.write( "12	<BR>\n" );
document.write( "8	<BR>\n" );
document.write( "14	<BR>\n" );
document.write( "9	<BR>\n" );
document.write( "11	<BR>\n" );
document.write( "16	<BR>\n" );
document.write( "7	<BR>\n" );
document.write( "9	<BR>\n" );
document.write( "12	<BR>\n" );
document.write( "10	<BR>\n" );
document.write( "1C	<BR>\n" );
document.write( "11<BR>\n" );
document.write( "(i)	Make a scatter plot to verify that it is reasonable to assume that the regression of y on x is linear<BR>\n" );
document.write( "(ii)	Fit a straight line by the method of least squares,<BR>\n" );
document.write( "(iii)	Estimate the moisture content when humidity is 45%.<BR>\n" );
document.write( "(iv)	Determine the correlation coefficient.\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #785847 by </B><A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><B>Edwin McCravy(20060)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><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=Edwin+McCravy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=785847\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "You can do all this with a TI-83 or 84.\r\n" );
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document.write( "Press the keys STAT 1 to put the x-values in L1,\r\n" );
document.write( "and the corresponding y-values in L2\r\n" );
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document.write( "Press STAT then press the right arrow key to highlight CALC.\r\n" );
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document.write( "To get a scatter plot press 2ND Y=  highlight ON choose the icon that\r\n" );
document.write( "looks like a scatter plot\r\n" );
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document.write( "To get the straight line press STAT then press the right arrow key to highlight CALC.  Choose LinReg(ax+b)\r\n" );
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document.write( "Substitute the values for a and b in y=ax+b for the\r\n" );
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document.write( "The value after \" r= \" is the correlation coefficient.\r\n" );
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document.write( "Substitute 0.45 in the equation.\r\n" );
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document.write( "Edwin</PRE> </SPAN>\n" );
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