Question

The table below shows the surface area y in square inches, of a shrinking puddle in x hours

Answer 1

Part A
Correlation coefficient: -.99
This tells us that as time goes on (value of x increases) the area of the puddle goes down (value of y decreases)

Part B
y₂ - y₁
-------   = slope
x₂ - x₁
9 - 15
--------
5 - 8
-6/-3 = 2
So the slope equals -2, regardless of the fact that we got 2 as an answer there, we know that it is a negative slope 

Part C
The data represents causation because an increase in the value of x results in a decrease in the value of y, this shows an example of direct causation between x and y.

Answer 2

Answer:

Step-by-step explanation:

Given is a table showing the surface area y in square inches, of a shrinking puddle in x hours

x y

 

2 25

5 15

8 9

11 2

 

r -0.993835256

Hence correlation coefficient is option B) -0.99

Part b:

Time Sur area

x y

 

2 25

5 15

8 9

11 2

 

r -0.993835256

slope -0.395083406

Intercept 11.53731343

slope =-0.395

Between 5 and 8, slope = $\frac{change in y}{change in x} \\=\frac{9-15}{8-5} \\=-2$

Slope represents the change of y with respect to 1 unit change in x.

Part c:

Yes correlation strong and negative.