Using the data in this table, what would be the line ofbest fit ( rounded to the nearest tenth)?

Solution
Note: The formula to use is
[tex]y=mx+b[/tex]Where m and b are given by
the b can also be given as
[tex]b=\bar{y}-m\bar{x}[/tex]The table below will be of help
We have the following from the table
[tex]\begin{gathered} \sum_^x=666 \\ \sum_^y=106.5 \\ \operatorname{\sum}_^x^2=39078 \\ \operatorname{\sum}_^xy=6592.5 \\ n=10 \end{gathered}[/tex]Substituting directing into the formula for m to obtain m
[tex]\begin{gathered} m=\frac{10(6592.5)-(666)(106.5)}{10(39078)-(666)^2} \\ m=\frac{-5004}{-52776} \\ m=0.09481582538 \\ m=0.095 \end{gathered}[/tex]to obtain b
[tex]\begin{gathered} \bar{y}=\frac{\operatorname{\sum}_^y}{n} \\ \bar{y}=\frac{106.5}{10} \\ \bar{y}=10.65 \\ and \\ \bar{x}=\frac{\operatorname{\sum}_^x}{n} \\ \bar{x}=\frac{666}{10} \\ \bar{x}=66.6 \end{gathered}[/tex]Therefore,
[tex]\begin{gathered} b=\bar{y}- m\bar{x} \\ b=10.65-(0.095)(66.6) \\ b=4.323 \end{gathered}[/tex]Therefore,
[tex]\begin{gathered} y=mx+b \\ y=0.095x+4.323 \end{gathered}[/tex]To the nearest tenth
[tex]y=0.1x+4.3[/tex]The least square method didn't give an accurate answer, so we use a graphing tool to estimate instead
Here
m = 0.5 (to the nearest tenth)
b = -23.5 (to the nearest tenth)
The answer is
[tex]\begin{gathered} y=mx+b \\ y=0.5x-23.5 \end{gathered}[/tex]