MHB Linear Equation Help: Plot, Find Eq., Approx Y for X=5

AI Thread Summary
To solve the problem of finding the equation of the best fit line and approximating y for x = 5, the data points provided (x: 0, 2, 4, 6, 7 and y: 2, 7, 14, 17, 20) should first be organized into a table. The regression equation can be derived using the formulas for the coefficients b0 and b1, which involve calculating the means of x and y, as well as the sums Sxy and Sxx. Users are encouraged to show their calculations for better assistance. The discussion emphasizes the importance of understanding the regression process to find the best fit line.
chanimal
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Hello,
i have been studying for finals and i am stuck on a question on my study guide. the question is to make a scatter plot of a set of data, find the equation of the best fit line, and approximate the value of y for x = 5.
the data is like this: x: 0 2 4 6 7
and the y is like : y: 2 7 14 17 20
if someone could help that would be great
 
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Hello and welcome to MHB! (Wave)

This question is better suited for our basic statistics forum, and so I will move it there when I finish posting.

We also ask that our users show what they have tried, so we can see where they are stuck and then we can provide better help that way.

First, let's represent the given ordered pairs in tabular form for improved readability:

[table="width: 100, class: grid, align: left"]
[tr]
[td]$x$[/td]
[td]$y$[/td]
[/tr]
[tr]
[td]0[/td]
[td]2[/td]
[/tr]
[tr]
[td]2[/td]
[td]7[/td]
[/tr]
[tr]
[td]4[/td]
[td]14[/td]
[/tr]
[tr]
[td]6[/td]
[td]17[/td]
[/tr]
[tr]
[td]7[/td]
[td]20[/td]
[/tr]
[/table]

Okay, now we need the following formula:

[box=blue]
Regression Equation

$$\hat{y}=b_0+b_1x\tag{1}$$

where:

$$b_1=\frac{S_{xy}}{S_{xx}},\quad b_0=\frac{1}{n}\left(\sum y-b_1\sum x\right)$$

$$S_{xx}=\sum(x-\overline{x})^2,\quad S_{xy}=\sum\left((x-\overline{x})(y-\overline{y})\right)$$
[/box]

I would begin by computing $\overline{x}$ and $\overline{y}$...what do you get?
 
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