Question 152574
X........Y
610.....915
631.....946
652.....978
673.....1009 

<pre><font size = 4 color = "indigo"><b>
Although it's not perfectly linear, it comes very
close.  To get the best fitting line, called the 
regression line, you have to plug those into a 
god-awful formula, but if you have a TI-83 or 
TI-84 calculator, you can get it easy.

From the cleared main screen,

Press STAT
Press ENTER

Type in the numbers for X in L1
Type in the numbers for Y in L2

Press STAT
Press right arrow
Press 4           ----> You should see LinReg(ax+b)
Press ENTER

Read this

LinReg
 y=ax+b
 a=1.495238095
 b=2.804761905
 
So the equation is Y=aX+b or

Y = 1.495238095X + 2.804761905

If you substitute 

X=610, you get Y=914.9 which rounds to Y=915
X=631, you get Y=946.3 which rounds to Y=946
X=652, you get Y=977.7 which rounds to Y=978
X=673, you get Y=1009.1 which rounds to Y=1009 

Edwin</pre>